Åbne vinduer med god lydisolation

Transcription

1 Åbne vinduer med god lydisolation Open windows with good sound insulation A Google-Translation, by Abel Harvie-Clark Original document can be found at: Environmental Project No Miljøprojekt nr Maj 2017

2 Publisher: Danish Environmental Protection Agency Editors: Lars Sommer Søndergaard Rune Egedal Morten Bording Hansen DELTA - a part of FORCE Technology illustrations: DELTA - a part of FORCE Technology HSHansen a / s photos: DELTA - a part of FORCE Technology ISBN: Disclaimer - When the occasion is given, the Danish Environmental Protection Agency will publish reports and reports on research And development projects in the environmental sector, funded by the Danish Environmental Protection Agency's investigation grant. It should be noted that such disclosure does not necessarily mean that the message in question expresses the views of the Danish EPA. However, the publication means that the Danish Environmental Protection Agency considers that the content constitutes a significant contribution to the debate on Danish environmental policy. Must be quoted with source statement. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 2

3 Contents 1. Foreword 5 2. Summary and conclusions (Danish) 6 3. Summary and conclusions (English) 7 4. Background What is the current situation? Project "Sound optimization of Air supply window" Need for solutions in addition to the Air supply window Purpose and delimitation Information retrieval Method Results Work Package T-shaped acoustic resonator Helmholtz resonator Quarter-wave resonator Hafencity Fenster - German designed air supply window Plenum window Work packages 2 and Margretheholm - external swivel sound coded Foil port - External sliding sound coded Experience with soundproofing open windows in traffic-loaded residential areas Literature review updated Window Type 1: "Air supply Window" Solution principle with improved absorbent Possible implementation Calculation of absorbents Resonator calculations Perforated absorbent calculations Laboratory measurements Resonator solution Perforated solution Variation of outer dimensions Collection Window Type 2: "Standard Window" with interior solution Development of the solution principle Laboratory measurements on mockup solution Dual solution Coarse solution summarized Side hinged solution 57 Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 3

4 8.2.4 Side-hanging solution summarized Development of prototype Laboratory measurements on prototype Collection Window Type 3: "Standard Window" with Exterior Solution " Development of solution principle Laboratory measurements on mockup solution Mockup Solution A Mockup Solution B Mockup Solution C The three mockup solutions compared Development of prototype Laboratory measurements on prototype Collection Field Measurement 10.1 Performing field measurements Results Laboratory measurements Results of laboratory measurements for comparison with field Results of additional laboratory measurements Comparison of field measurements and laboratory measurements Collection Measurement on traditional open windows and selected main results from the project Traditional open windows Selected results from the project Conclusion Appendix 1. References 122 Appendix 2. About the laboratory references 125 Appendix 3. Measurement Results in table form 128 Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 4

5 1. Preface Based on a previous project on air supply windows (Sound optimization of air supply windows) and an increasing need for sound insulation for open windows, a project called "Open windows with good sound insulation" has been completed. In general, three different window types are examined: I. Further development of the Air supply window II. Normal window with interior solution III. Normal window with exterior solution A considerable number of laboratory tests have been carried out with the various window types; both as mockup solutions and more finished prototype solutions as well as some field measurements. This report explains the measurements performed and the derived conclusions. The project was completed by DELTA - a part of FORCE Technology (DELTA) in cooperation with HSHansen a / s. The Danish Environmental Protection Agency has provided grants for the project in the form of project support within the grant scheme "Green Technology". The project group consists of Lars Sommer Søndergaard (project manager), Rune Egedal and Morten Bording Hansen from DELTA. In addition, Henrik S. Olesen and Dan Hoffmeyer - also from DELTA - have participated in the preparation of the project application and participated in some technical discussions during the course. From HSHansen a / s, Preben Knutsson and Michael Milert Hansen participated. The measurements were performed by Lars Sommer Søndergaard, Rune Egedal, Morten Bording Hansen and David Duhalde Rahbæk from DELTA. HSHansen a / s has among other things stood for the manufacture and assembly of the windows used. The project has been associated with a follow-up group consisting of Frank Pedersen and Jens Schultz Hansen, Environmental Protection Agency; Preben Knutsson, HSHansen a / s as well Lars S. Søndergaard, DELTA - a part of FORCE Technology. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 5

6 2. Sammenfatning og konklusioner Rapporten omhandler projektet Udvikling af vinduer med god lydisolation i åben tilstand gennemført af DELTA og HSHansen a/s. Projektet er medfinansieret af Miljøstyrelsen under udviklingsprogrammet Grøn Teknologi Projektet bygger videre på et tidligere projekt om russervinduer ( Lydmæssig optimering af Russervinduer ) [1]. Et almindeligt vindue har i åben tilstand en lav lydisolation, der for en del situationer ikke er tilstrækkelig for at opfylde kravene til indendørs støjniveau. Det primære formål med dette pro- jekt er at finde alternativer til et almindeligt åbent vindue, der både spænder bredt lydisolati- onsmæssigt, men også spænder bredt i forhold til dimensioner og placering af absorbenter og konstruktionsmæssige tilføjelser såsom en udvendig løsning. I projektet undersøges på baggrund af en indledende litteratursøgning tre forskellige vinduesty- per: I) Videreudvikling af russervinduet II) Almindeligt vindue med indvendig løsning og III) Almindeligt vindue med udvendig løsning. Der er gennemført et betydeligt antal laboratorieforsøg med de forskellige vinduestyper både som mockup-løsninger, som mere færdige prototypeløsninger og enkelte feltmålinger. Rappor- ten redegør for de udførte målinger og afledte konklusioner. Der er udviklet en optimeret udgave af russervinduet, her med specielt fokus på lydisolation for det lavfrekvente frekvensområde. I modsætning til tidligere er der udviklet perforerede kar- me, som er tunet til specifikt at håndtere den lavfrekvente del af spektret. Der er udviklet et vindue, der passer i et almindeligt vindueshul med en indvendig løsning. Med reference i et enkelt vindue ses forbedringer i flere step: først ved tilføjelse af et ekstra vindue (dvs. en samlet dobbeltkonstruktion), dernæst ved tilføjelse af et skydevindue i hulrummet og til sidst ved at tilføje absorption i karmkonstruktionen. Der er udviklet et vindue, der passer i et almindeligt vindueshul med en udvendig løsning,,og dermed ikke nødvendigvis fordrer, at der foretages ændringer på vindueshullet eller vinduet. Løsningen er baseret på en udvendig konstruktion i form af en påmonteret lydsluse, der har forbindelse til en vinduesramme, som åbnes ud i slusen. Der er udført sammenlignende felt- og laboratoriemålinger på et russervindue for at undersøge eventuelle forskelle mellem disse. Der ses en højere lydisolation for feltmålingerne end laboratoriemålingerne, specielt for frekvenser under 250 Hz. Forskellen i R w+c tr er 2-4 db. En forkla- ring kunne være forskellen i lydindfald, og det kan derfor ikke afvises, at forskellen kunne være større for vinduestyper, hvor åbningen i konstruktionen ikke vender mod støjkilden. For det samlede projekt kan det konkluderes, at der er arbejdet med tre vinduestyper, der spænder vidt i både lydisolation, dimensioner og konstruktion/løsningsprincip. For de tre vindu- estyper er opnået en laboratoriemålt lydisolation for R w+c tr på hhv. 26, 12 og 17 db, hvor et almindeligt åbent vindue har en lydisolation for R w+c tr på 5-8 db. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 6

7 3. Summary and conclusions This report covers the project " Udvikling af vinduer med god lydisolation i åben tilstand "( Development of windows with sound insulation in the open position ) conducted by DELTA and HSHansen a/s. The project is co-funded by the Environmental Protection Agency under the development program "Grøn Teknologi 2013" ( Green Technology 2013 ). The project is based on a previous project on "air supply windows" ("Lydmæssig optimering af Russervinduer ) ( Optimizing the sound insulation of air supply windows ) [1]. An ordinary window in an open position has a low sound insulation that for some situations are not sufficient to meet the Danish requirements to indoor noise level. The primary project objective is to research alternatives to an ordinary open window that both has wide-ranging sound insulation, but also are diverse in relation to dimensions, absorption material locations and structural additions such as an external solution. Based on an initial Literature review in the project, three different window types are assessed: I) Further development of the "Air supply window II) "Ordinary window" with an internal solution and III) "Ordinary window" with an external solution. A considerable number of laboratory measurements with different types of windows was con- ducted both as mockup solutions and more finished prototype solutions. The laboratory measurements were additionally supplemented by field measurements. The report presents the measurements and the subsequent conclusions. There is developed an optimized version of the "Air supply window" with a focus on sound insulation for low frequencies. In contrast to previously developed solutions, perforated casings tuned to dampen the low frequency part of the spectrum are developed. There is developed a window that fits in a standard window opening with an internal solution. With reference to a single window, improvements are seen in several steps: first by adding an additional window (i.e. overall double construction), next, by adding a sliding window into the cavity, and finally by adding absorption in the cavity of the window. There is developed a window that fits in a standard window opening with an external solution. It does not necessarily imply any changes to be made on the window hole or the window itself. The solution is based on an external design in the form of an attached sound-lock which is connected to a window frame that opens out into the sound-lock. Comparative field and laboratory measurements are conducted on an air supply window to investigate any differences between field and laboratory measurements. There is a higher sound insulation for field measurements than laboratory measurements, especially for fre- quencies below 250 Hz. The difference in R w+c tr is 2-4 db. An explanation could be the differ- ence in sound incidence. Hence it could be possible that the difference could be greater for window types in which the opening does not face the noise source. For the project, it can be concluded that three window types have been investigated, ranging widely in sound insulation, dimensions and design/solution principle. For the three window types, the laboratory sound insulation as R w+c tr was measured to respectively 26, 12 and 17 db with an opening area of 0.35 m 2. Laboratory sound insulation as R w+c tr for an ordinary open window are in the range of 5-8 db with an opening area of 0.35 m 2. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 7

8 4. Background 4.1 What is the current situation? In the Danish Environmental Protection Agency's Guide 4/2007: "Noise from roads" [30], there is - as a new introduction in Denmark - a requirement that a fixed noise limit for road traffic noise in certain situations must be possible indoors, with open windows. The noise limit must be met with windows opened to an opening area of 0.35 m2. With a moderate / high noise level outdoors from traffic, this can not be met with a traditional open window, but it requires special noise-absorbing window solutions. In 2007 requirements were also brought in for indoor noise with open windows from railways and businesses. Based on this background, DELTA, in cooperation with HSHansen a / s, conducted a project entitled "Sound optimization of air supply windows" [1] under the Danish Environmental Protection Agency's program "Grant for Environmentally Effective Technology 2008". Windows with good acoustic performance when open are highly useful for facade renovation or window replacement in, for example, existing residential properties, although these are not covered by the new requirement. In these situations, the outdoor traffic noise level may be high, for example db. The following two tables (Table 1 and Table 2) are derived from the Work Report from the Danish Environmental Protection Agency "New National Road Map Survey" (Tables 3.1 and 3.4) [21]. The tables show, among other things, that in Denmark there are 785,000 homes with a noise load above the indicative limit value of 58 db, 190,000 high-noise housing with a level above 68 db and approx. and 115,000 homes charged with over 70 db. Table 1 Number of noise-loaded homes 2007 divided into 5-dB intervals, excl. rural areas db Copenhagen area Rest of Denmark Total Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 8

9 Table 2 Number of noise-loaded homes 2007 by category Over 58 db Over 68 db Cities up to 1,000 inhabitants ,000-5,000 inhabitants ,000-20,000 inhabitants , ,000 inhabitants Over 100,000 inhabitants Other metropolitan areas Copenhagen county Copenhagen + Frederiksberg municipalities Rural areas Total Project Sound optimization of Air supply windows The first completed project "Sound optimization of "Air supply windows " was intended to develop design instructions for optimizing the sound insulation of the Air supply windows. A design guide was developed based on a significant number of laboratory measurements. Overall, the project was documented in three reports and two papers [1] [2] [3] [31] [32]. Extracts of the conclusions are shown below: "A Literature review was initially conducted with the purpose of uncovering what is found of relevant references in the field. The result of the relatively extensive Literature review is that systematic studies of sound insulation for this window type have not been performed previously. " "The dependence of sound insulation on parameters such as the window dimensions, opening area of the openings, window structure and various materials located in the cavity of the window have been investigated on the basis of a significant number of laboratory measurements. In addition, the importance of the window assembly was studied in practice, ie. Distance from the top of the window to ceiling and the ceiling's absorbent properties. " "The main conclusion of the project is that the main parameters of importance to the window insulation sound insulation are the height of the window, the opening area of the openings and the placement of sound absorbing material in the cavity of the window. Furthermore, the ceiling distance is important, especially if the ceiling is sound absorbing. It is found that comparing sound insulation to an open-ended, traditional window with a window-wrap window with the same opening area, the air supply window will have a sound insulation expressed as Rw + Ctr there - depending on the size and structure of the air supply window, is typically 8-16 db better than the sound insulation for the traditional window. It can therefore be concluded that the air supply window has acoustic advantages compared to an open-ended traditional window. " "The air supply window typically has the lowest sound insulation in the frequency range Hz. It is difficult to improve sound insulation in this frequency range - eg. By means of sound absorbers - as there will usually be limited space in the cavity of the window. It also appears that with 20mm and 40mm thickness absorbers, as used in this project, a significant improvement in sound insulation is achieved in the frequency range above 500Hz but only a limited effect at lower frequencies. It could therefore be relevant to investigate the possibility of designing special sound absorbers for use in air supply windows. As an alternative solution for improving sound insulation - especially in the low frequency range around the router resonance frequency - the possibility of using active noise suppression could be investigated closer. " "Based on the results of this report, a guideline entitled" Design guide for determining "window insulators" sound insulation has been prepared, "see reference. The conclusion states, among other things, that it will be useful to continue working with the Air supply window especially in order to improve sound insulation in the low frequency range Hz. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 9

10 4.3 Need for solutions in addition to the Air supply window There is also a need to evaluate / develop alternative solutions for the air supply window, since the window in certain situations has a sound insulation that is better than the requirement, and thus will be an unnecessarily expensive solution. Since the introduction of new regulations (item 4.1) included requirements regarding indoor noise with open windows, it is regularly reported by authorities, designers and window manufacturers that there is still a lack of knowledge and documentation in the area, as well as a lack of alternative, less expensive solutions. With an assortment of window possibilities, in those cases where only a little better sound insulation is required than what a plain window can handle, one does not have to choose an expensive solution with better sound insulation than necessary. To help with the noise requirement regarding Open windows, the Danish Environmental Protection Agency's Reference Laboratory for noise measurements has prepared an "Indoor noise level with open windows" orientation [20]. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 10

11 5. Purpose and boundary The purpose of this project is to further optimize the air supply window, primarily at low frequencies, and to suggest / develop alternative solutions either based on new principles or in the form of improvement of traditional windows sound insulation in open mode. The constructions that emerge through the project must be described and tested in a design so as to be as close to being "production mode" as possible. As mentioned in section 3.1, it has not been difficult to implement the new noise requirement with open windows. The requirement is applicable in connection with the arrangement of, inter alia, new housing and offices in areas with heavy traffic noise (58-68 db), which has not previously been permitted. It is especially about urban renewal, refill and revitalization of existing urban areas that the new possibilities are relevant. It is therefore important that the new requirements for indoor noise levels with open windows do not block these prospective possibilities because it proves difficult - potentially impossible - to provide window solutions that have sufficiently good acoustic performance when open. It is therefore important to go a step further with the development of windows with good soundproofing properties. With regard to improving the Air supply window's audio properties at low frequencies, the intention is to try with special sound absorbers in the cavity of the window. The absorbers must be specially optimized for high sound absorption in the low frequency range. Among other things, with more atypical absorbent types e.g. Narrowband absorbents such as Slotted or perforated types as well as absorbents based on the Helmholz resonator principle. In situations where there is no need for the sound insulation that the the air supply window can provide, devised / tested alternative solutions eg. Based on the improvement of traditional windows with different variants of sound cushions external or internal possibly combined with sound absorbers. The project therefore works with the following three main window types treated in each work package: - The Air supply window focusing on the low-frequency sound insulation (work package 1) - A common open window focusing on internal actions (work package 2) - A common open window focusing on external actions (work package 3) This project is based on windows made with frame / frame structures made of aluminum. However, it is estimated that all existing window types (wood, wood / aluminum, aluminum, steel and plastic) can be designed as the treated window types and that there are high degrees of freedom and variability in design and mechanical design. HSHansen a / s supplies and assembles the mockup models and prototype structure as well as for building and adaptation in the laboratory. Environmental Protection Agency / Open windows with good sound insulation Miljøstyrelsen / Åbne vinduer med god lydisolation 11

12 6. Literature review 6.1 Method In connection with the project "Sound optimization of 'Air supply windows'" [1], a Literature review has been conducted with the purpose of clarifying whether earlier audits of the air supply windows have been performed. In the current project, a renewed Literature review is initially made in order to determine whether there is new knowledge available since the search for the first air supply window project. In addition, the focus of the Literature review is centered on the three work packages in the project. The Literature review has been done by searching in various scientific databases for papers, articles, journals and books. Conferences such as Euronoise, Internoise, ICA and NoiseCon have been reviewed for relevant publications. References from the Literature review in [1] have been searched for whether researchers have since developed new knowledge. The Literature review covers three work packages, in which "Work Package 1" focuses on solutions aimed at improving the low-frequency sound insulation in the air supply window. Here, special attention is given to different types of absorbents and resonators. In connection with "Work Package 2", the Literature review is aimed at internal sound code solutions with natural ventilation. The Literature review for "Work Package 3" is aimed at external sound code solutions with natural ventilation, but is also focused on various absorbents and other damping solutions. General terms used for the search are for example: Plenum Window Dual airflow window HSIVW (High Sound Insulation Ventilating Windows) Acoustic ventilated windows Recessed Window Hafencity Fenster ( ) Acoustic window shutters T-shaped acoustic resonator Acoustic resonators in windows Helmholtz resonator in windows Low frequency acoustic resonator Micro perforated absorbers in windows In addition, the previously used terms have been searched: Ventilation Window, Air supply Window, Exhaust Air Window, Air Flow Window and Air Vented Window. 6.2 Results The result of the Literature review is summarized for each work package Work package 1 "Work Package 1" focuses on the improvement of the air supply window's low-frequency properties. In this regard, references for acoustic resonators have been found for the purpose of improving sound insulation in the low frequency range. Miljøstyrelsen / Åbne vinduer med god lydisolation 12

13 T-shaped acoustic resonator In reference [4] and [5], the effect of tuned T-shaped acoustic resonators is investigated in a square glass glass design for noise reduction in the 203 Hz-346 Hz frequency range. With a T-shaped resonator tuned to 203 Hz, an improved sound insulation of up to 14 db is achieved. The use of multiple resonators with different tuned frequencies is examined in reference [4] and [6] to achieve broadband attenuation. Reference [8] shows the results of a resonator array that is aimed at attenuating multiple resonant frequencies in a cavity of between 5-7 db in the low frequency range 145 Hz-249 Hz. References [4] and [6] show that the location of the resonator (s) is of great importance. Reference [6] shows a difference of 5 db in sound pressure level at different locations of resonators tuned to 145 Hz attenuation inside the cavity. It is important to note that reference [4], [5], [6] and [8] deal with resonators in enclosed cavities and that the changing state of the open and closed cavities in the windows window may need to be handled differently. For resonator dimensions, refer to reference [7] and [9] Helmholtz resonator In reference [10], the effect of Helmholtz resonators silencing properties is investigated in a doublepanel construction. The article provides several conclusions based on simulations, including the use of optimized Helmholtz resonators in a dual design, can improve sound insulation with 8 db in the frequency range 50 Hz-150 Hz using 1 resonator and 10 db using 3 resonators. It is concluded that the use of Helmholtz resonators is very robust to the angle of incidence of the sound. The maximum variation in sound insulation is 0.3 db. In reference [11] is presented the possibility of a dual Helmholtz resonator, which instead of placing two resonators for attenuation of two frequencies is a double Helmholtz resonator in one construction that attenuates two frequencies Quarter-wave resonator In reference [12], the effect of quarter wave resonators in a ventilation window is investigated, however, the relevance of this is limited as the improvement of sound insulation is in the 500 Hz - 4 khz frequency range. The necessary physical dimensions also mean that a more lowfrequency attenuation using quarter-wave resonators is not optimal Hafencity Fenster German designed air supply window Reference [13] deals with a Hamburg project with a window structure reminiscent of a window window. The structure of the Hafencity window is different from the window window, as the outside air enters the top of the window structure and is led into the room at the bottom of the window. The requirements for opening in Hamburg Hafencity are 4 cm [22]. The measurements of the Hafencity window are made with an opening area of m 2 and 0.11 m 2. A comparative measurement from the air supply window is with an opening of 0.14 m 2. Here the air supply window provides a sound insulation Rw (C; Ctr) of 18 (0; -2) db. The Hafencity window obtains a sound insulation Rw (C; Ctr) of 33 (- 1; -4) db with an opening area of 0.06 m2 and a sound insulation Rw (C; Ctr) of 31 (-2; -6) with An opening area of 0,11 m2. The soundproofing for the Hafencity window in the low-frequency advice100 Hz-250 Hz is between db, which is db better than the Air supply window in this frequency range [1]. Measurements are made according to DIN EN ISO with a separation area of 3 m Plenum window Reference [14] is a study of a window type resembling a horizontal windows window. The study is done on a 1: 4 aspect ratio and examines the importance of the angle of incidence of noise. The result of the study shows a difference of up to 7 db (A) in sound insulation depending on the angle of noise. Miljøstyrelsen / Åbne vinduer med god lydisolation 13

14 6.2.2 Modules of work 2 and Margretheholm sound coded external rotation Reference [15] has attempted an external audio codec solution that, when the window is opened, turns the sound pad in front of the opening. An opening area of at least 0.35 m 2 is maintained when the sound pad is at an angle of 45 degrees relative to the window. In an attempt where the opening area is 0.39 m 2, an R'w value of 19 db is measured Folehaven sound coded external slide Reference [16] has attempted an external audio codec solution for windows that open inward. The sound pad is mounted as a glass box outside the existing window. The audio code is mounted on a rail, so it is optional whether it is pushed aside or pushed for the window. In one outer position, the sound pad covers half of the two-winged rear window. In the other outer position, the sound pad covers the entire two-winged window. In the sides of the sound pad there is an approx. 3 cm crack, ensuring natural ventilation. Open area- Light is not 0.35 m 2. The sides of the sound pad are covered with sound-absorbing material. In a scenario, where the rear window is open, and the sound cushion is fully drawn to the window, a level difference between the outside (69 db (A)) and the inside (51 db (A)) of 18 db (A) Experiences with soundproofing windows in heavy traffic areas The State Building Research Institute of Birgit Rasmussen has prepared a report [17] and a paper [18] describing the need for soundproofing open windows in existing residential areas with a strong noise load from road traffic. On this basis and on the basis of government requirements for new housing, as well as experiences and comparisons from a number of Danish cases with soundproofing open windows, recommendations are given for initiatives to further develop window solutions that in open mode provide significantly better sound insulation than normal open windows. 6.3 Updated Literature review The above Literature review has been made in the initial stages of the project. During the project period, recent literature has been found that has been used when relevant. Miljøstyrelsen / Åbne vinduer med god lydisolation 14

15 7. Window type 1: Air supply window Illustration 7A. Photo of air supply window with perforated plates in the frame The air supply window is a well-known construction, which has been highlighted in a previous project for the Danish Environmental Protection Agency [1]. In the project, it was shown that a good effect can be achieved by adding absorbtion to the interior of the structure. However, it was also found that the effect obtained was limited to the higher frequencies and thus hampered the possibility of improving Rw + Ctr. In the project, tests were carried out with partially or partially absorbent cover panels and with a deeper absorbent to raise the level of low frequency absorption and thus also Rw + Ctr. The measurements performed earlier form the basis for the further development of the Air supply window, which has been made in this report. This report focuses on further developing the design so that it functions more absorbent at lower frequencies in the frequency range below Hz. 7.1 Solution principle with improved absorbent in the frame The original design of the windows window was based on the purpose of optimizing the design effect for the low-frequency sound insulation. Focusing on a solution that will not affect the effective airflow area of the structure. To avoid blocking the airflow area, optimized on the frame structures with starting point in low-frequency attenuation. Initially, a test was made as to whether a deeper absorbent in the frame would have an effect on the low frequency range. This was investigated by opening to the surrounding hollow wall and thus exposing the mineral wool between the two wall halves. Comparative measurements were made, which were partly closed to the cavity wall and partly absorbed absorbent based on the previous report [1]. As in the previous project, the Sund Environmental Underlay (SUND ) plate absorber is used as an absorbent material in thickness either 20 mm or 40 mm. The results of the measurements will generally be presented in a figure as FIGURE 1. The figure shows the reduction number indicated in a 1/3 octave graph. Likewise, the measurement Miljøstyrelsen / Åbne vinduer med god lydisolation 15

16 Reduction rate, R [db] number will be shown immediately to the right. Below the graph, a brief description of the measurement is displayed as well as the single value Rw and Rw + Ctr. The description of the laboratory layout is explained in Appendix 2. All single-value values for all measurements are indicated by the measurement number in Appendix 3. Measuring results in table form. FIGURE 1. Examine the effect by opening the frame vs. closed to hollow wall with or without SUND absorbent. The window is always open with 0.35 m ( M 1001 ) 50 ( M 1005 ) 40 ( M 1007 ) 30 ( M 1008 ) Frequency [Hz] Measurement no. Rw Rw+Ctr Description (location and absorbers) [db] [db] M Open to hollow wall with mineral wool M Closed to hollow wall with plasterboard M Closed to hollow wall with plasterboard + 20 mm SUND M Closed to hollow wall with plasterboard + 20 mm SUND Miljøstyrelsen / Åbne vinduer med god lydisolation 16

17 It is clearly seen from the measurements in figure 1 that a significantly greater absorption is introduced by opening directly to the cavity wall. It is also seen as expected that the measurements have a coincidence of up to about Hz, after which - depending on the thickness of the absorbent - for the high frequency the same level is achieved as the measurement of the open-wall insulation (here the mineral wool in the double plasterboard wall). This initial measurement underlies the solution principles that are focused on the further development of the air supply window. An open hole wall is not realistic in a final solution, and it focuses on changing the frames so that they are tuned to the low frequency range, thus ideally illuminating an open hole wall. The focus is on the following solutions: - Increased depth of field with space for porous absorber together with perforated frame. - Helmholtz resonators located in the frame, tuned to specific frequencies. Miljøstyrelsen / Åbne vinduer med god lydisolation 17

18 7.2 Possible implementation In order to have deeper absorbtion in the frame that can resemble the open hole wall, a box that can be inside the hollow wall is constructed, see Illustration 7B. Cavity/ box at the top Cavity/box at the bottom Cavity/ box on left and right side Illustration 7B. Sketch of window and frame structure for the windows window. At the top left, the design is shown in its entirety. At the top right is a vertical section of the structure, with the boxes at the top and bottom clearly visible. At the bottom is a cross section of the structure, with the boxes on the sides clearly visible. This box should provide the opportunity to combine absorption materials and make sure that the hole is closed. The box must be of appropriate depth so that the absorbers can be tuned to the desired frequency range. Miljøstyrelsen / Åbne vinduer med god lydisolation 18

19 It is desired that the absorbents are effective from Hz and below. This implementation means that the window does not immediately "grow" in size, but keeps the dimensions previously worked. To make such a solution easier to assemble, the boxes could be incorporated as part of the window structure, so that the side would have two opaque boxes mounted on the window. The laboratory is working with a cash solution. The solution is implemented in all four frames, allowing you to take advantage of the additional depth of field on all four sides. In the laboratory, the maximum achievable depths (limited by the current structure in the laboratory) have been selected on the boxes. This means that the depth of the sides is 410 mm, for the bottom 300 mm and for the top 170 mm. These goals are also the basis for further calculations. 7.3 Calculation of absorbents As mentioned in section 7.1, two types of absorbents have been selected for implementation, respectively. A resonator-based solution and a combined solution of porous material together with perforated plates. Below are the results of the calculations for the different types of absorbent Resonator calculations In the literature study in section 6.2.1, different resonators have been found. So-called "T-shaped resonators" and the usual Helmholtz resonators. Since it is important to avoid unnecessary space absorption, the most compact of the two solutions, as in this case, is the "T-shaped resonator". The resonator consists of 4 elements: one neck (branch 1), one T-joint and two end pieces, one of which is short (branch 2) and the other long (branch 3), as seen in illustration 7A. These are the items that are regulated to tune the resonator to the desired frequency. Branch 1 Branch 2 Branch 3 Illustation 7C. T-shaped resonator principle [7] In order to make the calculations and ultimately the implementation equally, it is chosen to work with 3 fixed-defined elements and an adjustable element, all of the same diameter. With reference to Figure 7C, the length of branches 1 and 2 and the size of the T-piece are maintained, whereas the length of branch 3 is variable. Calculations are carried out on the basis of the publications found in the literature study (see section 6.2.1). Lengths of branch 3 with different diameters of the total resonator are calculated to find optimal location and space requirements. Table 3 shows the calculations for a setup with a diameter of ø50mm for all three branches. The calculations have been based on finding a suitable resonator size. Therefore, calculations have been performed for different resonant frequencies as well as different diameters of the resonator structure. The resonance frequency is the frequency at which the resonator will have a damping effect. Miljøstyrelsen / Åbne vinduer med god lydisolation 19

20 Table 3. The length of respectively. Branches 1 and 2 are fixed at 50 mm. The length of branch 3 is calculated and is given here in meters. Diameter/Frequency 100 Hz 150 Hz 200 Hz 250Hz 300 Hz 350 Hz 400 Hz ø12 mm 0.79 m 0.51 m 0.36 m 0.28 m 0.22 m 0.17 m 0.14 m ø16 mm 0.79 m 0.50 m 0.36 m 0.27 m 0.21 m 0.17 m 0.13 m ø20 mm 0.79 m 0.50 m 0.35 m 0.27 m 0.21 m 0.16 m 0.13 m ø25 mm 0.78 m 0.49 m 0.35 m 0.26 m 0.20 m 0.16 m 0.12 m ø32 mm 0.77 m 0.49 m 0.34 m 0.25 m 0.19 m 0.15 m 0.11 m ø50 mm 0.75 m 0.47 m 0.32 m 0.23 m 0.17 m 0.12 m 0.08 m ø63 mm m 0.45 m 0.30 m 0.21 m 0.15 m 0.10 m 0.05 m The calculated values provide the basis for the dimensioning of the resonators for use in the construction. To make resonators easy to set, branch 3 is made as long as possible, but with the option of inserting a plug that can adjust the length without cutting any of the tube Perforated absorbent calculations The perforated solution is already known, as it is currently used especially in ceilings and also in other contexts. The principle is based on the principle of Helmholtz, as with the resonators. Here, in contrast to the above, there are several gaps, and in order to decrease the frequency, there is also a need for a larger cavity, as opposed to what is the case for the calculated resonator (T-shaped resonator). However, it gives an opportunity to tune the perforated plates into a wider area so the absorption itself is not as narrow as the resonator. The calculations are based on [23], which describes the design process for perforated absorbents. The starting point is to dampen frequencies below 350 Hz while making it as wide as possible with the targets available in the laboratory. To achieve a broader frequency range where the absorption is high, two perforation levels are calculated through the window. The calculations only apply to the perpendicular occurrence. In addition, the perforated plates are made of 13 mm gypsum board with a 5 mm hollow radius. Depending on the perforation degree, the distance between the holes varies. For the low perforation degree, the distance from the center to the center of the holes is 50 mm, while the height is 15 mm. It gives a perforation rate of respectively. 3.14% and 34.91%. Illustrations 7E and 7F show the different perforation degrees mounted in the window. In FIGURE 2, the absorption coefficient is calculated in the areas where the depth of the frame is 410 mm. The frame is filled with mineral wool with an air flow resistance of 9000 Rayls / m. The calculations for two perforation rates are shown. It can be seen from the calculations that a combined absorption coefficient of more than 0.8 can be expected in the range of 100 Hz to 1750 Hz. Miljøstyrelsen / Åbne vinduer med god lydisolation 20

21 Absorption α [-] FIGURE 2. Calculation of absorption coefficient depending on perforation degree with 410 mm mineral wool. 1,00 0,90 0,80 0,70 0,60 0,50 0,40 2 0,30 0,20 0,10 0, Frequency [Hz] 1 Calculation no. Description (Perforation degree and cavity depth) 3,14 % 410 mm mineral wool 1 34,91 % 410 mm mineral wool In FIGURE 3, in comparison with FIGURE 2, a similar calculation is seen. In this case, it is calculated for a 170 mm cavity filled with mineral wool with a flow resistance of 9000 Rayls / m. The calculation applies to the upper frame as there is no greater depth than 170 mm. It can be seen that depending on the degree of perforation chosen, low frequency absorption can be achieved in a narrow frequency range or absorption in a wider range at higher frequencies. Since the width of the upper frame is only 1250 mm, there is no combined absorption as in the sides. Miljøstyrelsen / Åbne vinduer med god lydisolation 21

22 Absorption α [-] FIGURE3. Calculation of absorption coefficient depending on perforation degree with 170 mm mineral wool. 1,00 0,90 0,80 0,70 0,60 0,50 0,40 4 0,30 0,20 0,10 0, Frequency [Hz] 3 Calculation no. Description (Perforation degree and cavity depth) 2 3,14 % 170 mm mineral wool 3 34,91 % 170 mm mineral wool In FIGURE 4, it is calculated with a 300 mm cavity filled with mineral wool with an air flow resistance of 9000 Rayls / m. Unlike in FIGURE 3, it is seen that the absorption value of the two perforations assumes a broader shape but with a very low absorption coefficient. The calculation is done for the bottom frame in the window, where the maximum depth is 300 mm. Miljøstyrelsen / Åbne vinduer med god lydisolation 22

23 Absorption α [-] FIGURE4. Calculation of absorption coefficient depending on perforation degree with 300 mm mineral wool. 1,00 0,90 0,80 0,70 0,60 0,50 0,40 6 0,30 0,20 0,10 0, Frequency [Hz] 5 Calculation no. Description (Perforation degree and cavity depth) 4 3,14 % 300 mm mineral wool 5 34,91 % 300 mm mineral wool It is possible to change the absorption values by using, for example, a porous material with a greater airflow resistance than the one used. It is also possible to work with, for example, semifilled cavities combining air with a porous material. Calculations have been performed where the mineral wool has not filled the entire cavity. The calculations shown are the combination most commonly used in the project. 7.4 Laboratory measurements In the laboratory, measurements have been performed for the two types of solution, respectively. A solution based on T-shaped resonators and on perforated plates with porous filling in the cavity cavity. The dimensions with resonators are performed in the window size (width x height) 1250 mm x 2100 mm. The measurements with perforated plates and porous frames are made in three different sizes of the windows window respectively mm x 2100 mm, 1250 mm x 1500 mm and 900 mm x 2100 mm. Miljøstyrelsen / Åbne vinduer med god lydisolation 23

24 Illustration 7D. Photos of the window with inserted resonators. Left photo shows the resonators mounted in the vertical frame, while the right photo shows the resonators mounted in the horizontal frame (bottom). In illustration 7D the mounting of the resonators in the frame is seen. The resonators are built in general plastic drain pipes sealed with silicone. The resonators are as far as possible located after the standing waves that appear in the closed window at the selected frequencies for the resonators. Miljøstyrelsen / Åbne vinduer med god lydisolation 24

25 Illustration 7E. Photo of the window fitted with 34.91% perforated frame. The picture shows the upper corner. Illustration 7F. Photo of the window fitted with 34.91% and 3.14% perforated frame. Top and bottom. The photo is of the bottom of the window. In the illustrations 7E and 7F, the window is shown with perforated plates with porous filling. The two illustrations are both shown for the window with the dimensions (width x height) 1250 mm x 2100 mm. In these illustrations, the sides are clad with respectively % perforation at the top and 3.14% perforation at the bottom. Top and bottom frames are respectively % and 3.14% perforated. As mentioned earlier, the perforated plates are made of 13 mm plasterboard. Miljøstyrelsen / Åbne vinduer med god lydisolation 25

26 The illustrations shown are examples of how it may look. In the measurements, it is performed with different settings and combinations. In addition to the perforated plates, there are also experiments with the use of absorbent not on the perforated plates Resonator solution For the resonator solution, the window is considered a closed box in connection with the location of the resonators. As far as possible, it is attempted to position the resonators based on the quartz lengths corresponding to the frequency at which the resonators have been tuned. In addition, trials and corners have been tried. Referring to FIGURE 5, a larger number of resonators have been tuned to the same frequency and two consecutive 1/3 octave frequencies that, relative to the solution without resonators, there is no difference in Rw + Ctr between them and a solution where the frame is closed with plasterboard. The resonators are all tuned to the higher part of the low-frequency spectra, respectively. 200 Hz and 315 Hz. During the laboratory measurements, stationary source measurement (as opposed to the movable speaker usually used in the laboratory), and narrowband noise measurement, were attempted. For these measurements, no significant effect is seen. However, a minor difference can be seen when testing with interest rates at the current frequencies of the resonators. In FIGURE 6, the measurements are made with a lower frequency for the resonators. As with the measurements in FIGURE 5, no improvement of Rw + Ctr is seen relative to the reference level where the frame is a gypsum board. It is possible that the location of the resonators has not been optimal. A thorough simulation of the acoustic field in the open and closed window would be able to help select the optimal placement of the resonators. However, such a simulation has not been possible within the framework of the project. However, such simulation could contribute to a possible improvement of sound insulation. The results obtained in these measurements are comparable to the results obtained in the former non-absorbent stainless steel window project [1]. Miljøstyrelsen / Åbne vinduer med god lydisolation 26

27 Sound Reduction, R [db] FIGURE 5. Window opened 0,35 m 2. Various resonator settings fitted with plasterboard 60 ( M 1208 ) 50 ( M 1210 ) 40 ( M 1213 ) 30 ( M 1214 ) 20 ( M 1216 ) 10 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M resonators in the sides, tuned to 200 Hz M resonators in the sides, tuned to 200 Hz M resonators in the sides, 2 tuned to 315 Hz and 4 ti 200 Hz M resonators, 2 in the top frame, tuned to 315 Hz og 4 in the sides, tuned to 200 Hz M Closed with plasterboad against the barracks Miljøstyrelsen / Åbne vinduer med god lydisolation 27

28 Sound Reduction, R [db] FIGURE 6. Open window 0,35 m 2. Resonators of different settings mounted at either the top or bottom of the window. 60 ( M 1108 ) 50 ( M 1109 ) 40 ( M 1110 ) 30 ( M 1111 ) 20 ( M 1216 ) 10 0 Frequency [Hz] Measurement no. R w R w+c tr Description (location and absorbers) [db] [db] M resonators at the bottom, tuned to 80 Hz M resonator at the left side of the bottom, tuned to 80 Hz M resonators at the top, tuned to 80 Hz M resonators at the top, tuned to 200 Hz M Closed with plasterboad against the barracks Perforated solution Calculations have been performed for perforated absorbents with different perforation rates, as described in section 7.3. Initially, measurements have been made with a constant perforation degree. In addition, with and without mineral wool is tested in the cavity and perforation only partially in the vessels. In FIGURE 7, measurements are performed with a constant perforation rate of 3.14%. Initially, there are perforated plates in the sides with a cavity filling with mineral wool. Hereafter, there are additional mounted perforated plates in the top and bottom still with the same degree of perforation, however, respectively with air and mineral wool in the cavity. Miljøstyrelsen / Åbne vinduer med god lydisolation 28

29 Sound Reduction, R [db] FIGURE 7. Open window 0,35 m 2. Perforated plates with a perforation degree of 3.14%, different filling in cavities and various perforated frames. 60 ( M 1216 ) 50 ( M 1304 ) 40 ( M 1310 ) 30 ( M 1317 ) Frequency [Hz] Measureme nt no. R w [db] R w+c tr [db] Description (location and and absorbersr) M Closed with plasterboad against the barracks M The sides perforated 3.14%, cavity filled with mineral wool M Top and bottom perforated 3.14%, cavity with air, sides perforated 3.14%, cavity with mineral wool M Top and bottom perforated 3.14%, cavity with mineral wool, sides perforated 3.14%, mineral wool cavity From the calculations, it is seen that there should be a higher absorption from about 500 Hz and down to 50 Hz with a perforation of 3.14%. From FIGURE 7 it is seen that the reduction rate from 500 Hz and below for the perforated measurements is increased relative to the standard solution with ordinary plasterboard. It is also seen that for 500 Hz and above, the reference measurement and the perforated measurements coincide, indicating that the calculated effects from the perforated plates are what is seen in the measurement. It is also seen that Rw and Rw + Ctr have increased by 1 db relative to the reference measurement. It is a modest increase, but it is found solely by regulating the low-frequency range of window. Miljøstyrelsen / Åbne vinduer med god lydisolation 29

30 Sound Reduction, R [db] In the previously conducted Air supply window project, it has been found that common porous absorbents in the frame have a beneficial effect for the absorption of Frequencyer over 500 Hz. Measurements are made where absorbents are applied outside the perforated plates to increase the absorption at higher frequencies. The same absorbent is used as in the previously performed project (SUND ). In FIGURE 8, the measurements are performed with a solid perforation of 3.14% in the sides. Measured with and without SUND absorbent in the frames. The measurements show that the Frequency Range over 500 Hz is increased without the lowfrequency gain found by perforating the plates disappearing. However, there is a small loss in the low-frequency range when there is no absorbent. It is seen that for both 20 mm and 40 mm the frame is absorbent a Rw of db versus 19 db and a Rw + Ctr of 21 versus 18 db is achieved, which is an increase of 3 db relative to a solution Without absorbent. FIGURE8. Open window 0,35 m 2. Perforated plates with a perforation degree of 3.14%, only the sides are perforated, the frames are with and without clothing of SUND. 60 ( M 1216 ) 50 ( M 1304 ) 40 ( M 1306 ) 30 ( M 1307 ) Frequency [Hz] Measureme nt no. R w [db] R w+c tr [db] Description (location and absorbers) M Closed with plasterboad against the barracks M Cavity filled with mineral wool M Cavity filled with mineral wool, covered with 40 mm SUND M Cavity filled with mineral wool, covered with 20 mm SUND Miljøstyrelsen / Åbne vinduer med god lydisolation 30

31 The measurements carried out so far have all been with the same perforation rate. In section calculations have also been performed with a greater perforation rate than the 3.14%. The idea of the greater perforation rate is to cover a wider frequency range of the absorbent. Combining the two of the perforation achieves a greater coverage and thus an expected better reduction rate. In FIGURE 9, measurements are performed with and without combined perforation degree. It is seen that there is a coincidence between the measurements for the lowest frequencies and again for the highest frequencies. It is also seen that for the measurements where either the top or bottom have been with a higher degree of perforation, a higher absorption for the intermediate frequencies has been achieved than when the window is only fitted with 3.14% perforation degree. With a perforation degree of 34.91% in either top or bottom, 1 db extra in Rw + Ctr is obtained relative to a perforation rate of 3.14% at all. Equally, an increase of 2 db Rw + Ctr is achieved with respect to a structure without perforated arms. Miljøstyrelsen / Åbne vinduer med god lydisolation 31

32 Sound Reduction, R [db] FIGURE9. Open window0,35 m 2. The sides are perforated 3.14%. Top and bottom frames made with different perforation degrees. 3.14% and 34.91%. 60 ( M 1216 ) 50 ( M 1317 ) 40 ( M 1318 ) 30 ( M 1319 ) Frequency [Hz] Measurem ent no.. R w [db] R w+c tr [db] Description (location and absorbers) M Closed with plasterboad against the barracks M Top and bottom perforated 3,14 % to cavity with mineral wool, sides perforated 3.14% to cavity with mineral wool M Bottom perforated 34,91 % to cavity with mineral wool, top and side perforated 3,14 % to cavity with mineral wool M Top perforated 34,91 % to cavity with mineral wool, bottom and sides perforated 3,14 % to cavity with mineral wool An improved distribution of the perforated areas has been attempted. Instead of placing only the high degree of perforation at the bottom or top, it is also inserted into the side frame of approx. 2/5 of the length of the frame. Of course, simulations of the acoustical field of the window can be achieved with a better location of the various absorbents. However, in these measurements, only the intention is to show the principle and not optimize the location. In FIGURE 10, the measurements are performed with combined perforation degree while the porous absorbent is inserted on the perforated plates. By introducing a larger perforation degree in the core sides at the same time as a greater perforation rate at the bottom, the area with increased absorption increases from not only at lower frequencies but to span the entire area. Miljøstyrelsen / Åbne vinduer med god lydisolation 32

33 Sound Reduciton, R [db] Porous absorbent is applied to the frames to achieve better attenuation at the Higher Frequencyer. As before, it is seen that the area over 500 Hz increases while some of the effect of the perforated low frequency sheets disappears, yet they are still functioning as seen when the measurements are compared to a non-perforated solution. It is also seen that both the 20 mm and 40 mm SUND achieve the same result with a Rw value of 25 db and a Rw + Ctr of 22 db, a total increase of 4 db Rw + Ctr compared to a non-perforated solution. The solution here can be seen as the optimal solution for surfaces where absorbent can be placed as all glass fields are kept without absorbent. FIGURE10. Open window 0,35 m 2. The sidesr are perforated 3,14 % 3/5 of the frame, the remaining 2/5 is Perforated 34.91%. The top is Perforated 3.14% and bottom 34.91%. 60 ( M 1216 ) 50 ( M 1401 ) 40 ( M 1402 ) 30 ( M 1403 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M Closed with plasterboad against the barracks M Perforated, Cavity filled with mineral wool M Perforated, Cavity filled with mineral wool, 20mm SUND M Perforated, Cavity filled with mineral wool, 40mm SUND Miljøstyrelsen / Åbne vinduer med god lydisolation 33

34 However, there may be urban areas where it is necessary to have a very high reduction rate. To illuminate the full potential of the window, measurements with absorbent are located on some of the transparent surfaces. In order to still work with a solution that shuts light on and ensures that the solution is comfortable for the user, there have been only attempts with absorbents located on the openings and on the opposite side of the opening, see Illustration 7G. In FIGURE 11, it is seen that by implementing absorbent on open-up and opposing window, a R w of 29 db and R w + C tr of 24 db is obtained. It is also seen that there is no difference whether it is 40 mm or 20 mm mounted on the frames. Finally, a measurement has been made where the opposite sides in relation to the opening are filled as much as possible with absorbent. This solution should be seen as an absolute max. Measurement, where it is still possible to look through the window. Here, a R w of 30 db and R w + C tr of 26 db is achieved - a total improvement relative to the window without 11 db absorbance for R w and 8 db for R w + C tr. Illustration 7G. Left side: Photo seen from the inside of the absorbent on the upholstery and the window facing upholstery. Right side: Photo seen from outside side of absorbent on the upholstery and window facing upholstery. Miljøstyrelsen / Åbne vinduer med god lydisolation 34

35 Reduktionstal, R [db] FIGURE11. Open window0,35 m 2. The sides are perforated 3.14% 3/5 of the frame, the remaining 2/5 are perforated 34.91%. The top is perforated 3.14% and bottom 34.91%. All cavities are filled with mineral wool. 60 ( M 1216 ) 50 ( M 1404 ) 40 ( M 1405 ) 30 ( M 1406 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M Closed with plasterboad against the barracks M Perforated, 40 mm SUND on the frames, 20 mm SUND on the upholstery and opposite window for openings M Perforated, 20 mm SUND on the frames, 20 mm SUND on the upholstery and opposite window for openings M Perforated, 40 mm SUND on the frames, 20 mm SUND on the cover As well as 80 mm at the top and 40 mm at the bottom of the opposite window for opening Variation of outer dimensions All measurements shown in FIGURE5-FIGURE11 are performed on a window of the same dimension (width x height) 1250 mm x 2100 mm (2.63 m 2 ). This solution is somewhat demanding, and it is therefore considered which possibilities are available with windows built up as the window window, however, with other dimensions. Measurements are carried out on the windows with dimensions (height x width) 1250 mm x 1500 mm (1.88 m 2 ) and 900 mm x 2100 mm (1.89 m 2 ). Miljøstyrelsen / Åbne vinduer med god lydisolation 35

36 Noise Reduction R [db] Initially, measurements have been performed with the windows closed. It is done to see if there is a clear difference between the windows in general. In FIGURE 12, the measurements of the various windows are seen in the closed state, without the addition of any kind of absorption in the window. It is seen that the windows are monitored at low frequency. It is also seen that from 500 Hz the low of the three windows differs as the slightest, while the two constructions of the same height but different width are closely followed FIGURE12. Closed window. The various dimensions of Air supply window. The measurements are only orientated as there is no correction for flank transmission. 80 ( M 1004 ) 70 ( M 1501 ) 60 ( M 1601 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M Closed with plasterboad against the barracks, No absorbents 1250 mm x 2100 mm M Closed with plasterboad against the barracks, No absorbents 1250 mm x 1500 mm M Closed with plasterboad against the barracks, No absorbents 900 mm x 2100 mm The different dimensions are desired compared to the open state. However, due to the construction of the narrow high window, it is not possible to compare the measurements in full, as the window can only be opened 0.28 m 2. Miljøstyrelsen / Åbne vinduer med god lydisolation 36

37 In FIGURE 13, the measurements are performed on the three different windows. It is based on a solution where there is no absorbent and a solution that contains both perforated plates and porous absorbent. The measurements are similar to the closed measurement that the two high constructions stand out. They perform about 3 db better Rw + Ctr compared to the short, wide window. However, it is assumed that the opening of 0.28 m 2 for one window is important. Even though this is taken into account, there is a clear tendency that the higher the construction, the better it is, the window is even better, there is a longer way for the sound. Miljøstyrelsen / Åbne vinduer med god lydisolation 37

38 Noise Reduction, R [db] FIGURE13. Open window0,35/0,28 m 2. Impact of perforated absorbents for different dimensions. 60 ( M 1401 ) 50 ( M 1504 ) 40 ( M 1604 ) 30 ( M 1216 ) 20 ( M 1502 ) 10 ( M 1602 ) 0 Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M The bottom is perforated34,91 %, top 3,14 %, sides 3/5 perforated 3,14 % and 2/5 perforated 34,91 % Cavity filled with mineral wool mm x 2100 mm M The bottom is perforated34,91 %, top 3,14 %, sides 1/3 perforated 3,14 % and 2/3 perforated 34,91 % Cavity filled with mineral wool 1250 mm x 1500 mm M The bottom is perforated34,91 %, top 3,14 %, sides 3/5 perforated 3,14 % and 2/5 perforated 34,91 % Cavity filled with mineral wool 900 mm x 2100 mm M Closed with plasterboad against the barracks 1250 mm x 2100 mm M Closed with plasterboad against the barracks 1250 mm x 1500 mm M Closed with plasterboad against the barracks 900 mm x 2100 mm For the measurements shown in FIGURE13, as for the other measurements, in order to increase the absorption at the higher Frequencyer, porous absorbent is applied to the frames. This leads to the measurements set forth in FIGURE14. It is seen from the measurements of the high, narrow window and for the low window that a high absorption is obtained at the higher frequency. Miljøstyrelsen / Åbne vinduer med god lydisolation 38

39 Also, it is seen that there is a comparable gain in introducing the absorbent to both the high and the low windows. Here an increase is achieved on respectively. 5 db for Rw and 3 db for Rw + Ctr for the high window and respectively. 3 db for Rw and 3 db for Rw + Ctr for the low window. This is probably due to the fact that the amount of applied absorbent area is near the same. Miljøstyrelsen / Åbne vinduer med god lydisolation 39

40 Noise Reduction, R [db] FIGURE14. Open window0,35/0,28 m 2. Different dimensions of the stainless steel window with perforated absorbents and SUND. 60 ( M 1505 ) 50 ( M 1506 ) 40 ( M 1507 ) 30 ( M 1605 ) 20 ( M 1606 ) 10 ( M 1607 ) 0 Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M The bottom is perforated34,91 %, top 3,14 %, sides 1/3 perforated 3,14 % og 2/3 perforated 34,91 %, cavity filled with air, 1250 mm x1500 mm M The bottom is perforated34,91 %, top 3,14 %, sides 1/3 perforated 3,14 % og 2/3 perforated 34,91 % cavity filled with air, 20 mm SUND on the frame,1250 mm x 1500 mm M The bottom is perforated34,91 %, top 3,14 %, sides 1/3 perforated 3,14 % og 2/3 perforated 34,91 %, cavity filled with air, 40mm SUND on the frame,1250 mm x 1500 mm M The bottom is perforated34,91 %, top 3,14 %, sides perforated 3/5 3,14 % og 2/5 perforated 34,91 %, cavity filled with air, 900 mm x 2100 mm M The bottom is perforated34,91 %, top 3,14 %, sides 3/5 perforated 3,14 % og 2/5 perforated 34,91 %, cavity filled with air, 20 mm SUND on the frame, 900 mm x 2100 mm M The bottom is perforated34,91 %, top 3,14 %, sides 3/5 perforated 3,14 % og 2/5 perforated 34,91 %, cavity filled with air, 40 mm SUND on the frame, 900 mm x 2100 mm Miljøstyrelsen / Åbne vinduer med god lydisolation 40

41 7.5 Conclusion This part of the project is based on the earlier construction of the "Air supply window". The solution is based on the same format as before. However, the idea of this work package was to increase the reduction rate by increasing the absorption in the lowfrequency range. Initially, calculations have been made for both a resonator-based solution and a solution with perforated plates as well as performed measurements with an exposed hole in order to indicate whether this could increase the low-frequency absorption. Opening to the cavity was an improvement of Rw + Ctr of 8 db relative to the clean plasterboard in the frame and 4 db in comparison with measurements using 40 mm SUND on the frame. A large number of measurements have been performed in the laboratory on both the resonator-based solution and the perforated solution. For the resonator-based solution, there was no gain by inserting resonators into the frame. However, measurements with interest rates have shown that they could be attenuated. The measurements performed for the perforated solutions show good results, and improvements are also seen in the Frequency areas where the calculations predicted the improvements. There is a difference in the reduction rate at low Frequencyer, while the reduction rate at the higher Frequencyer is the same order of magnitude as in the solution where the boxes are closed with plasterboard. To increase the maximum single value, use the conclusions found in the previous project and install SUND absorbent without on the perforated plates. An improvement of Rw + Ctr is achieved at 2 db compared to a set-up without perforated plates with 40 mm SUND. By increasing the amount of absorbent in the window by placing the SUND on the top and the opposing glass is achieved, an improvement for Rw + Ctr of 8 db is achieved relative to a frame fitted with plasterboard. A number of measurements have been performed with different window dimensions. The results show, as in the first Air supply window project, that it is important to have a good height in the window and thus a long "way" for the sound to wander. There is a difference between a high and low window of Rw + Ctr of 3-4 db. For the two types of construction tested, only an improvement can be found with the perforated plates. For the resonator solution, there was no improvement over the first Air supply window project. For the perforated solution, there is a clear difference to the previous project. A 22wb Rw + Ctr has been obtained for the perforated solution with 20mm SUND. In the previous project, the Rw + Ctr value with 20 mm SUND was 19 db. It indicates an increase of 3 db. Comparing the two maximum measurements from the earlier and this project, an increase from a Rw + Ctr of 24 db to 26 db is seen. It indicates an increase of 2 db. These increases in the reduction figure were found solely by introducing perforated plates. Miljøstyrelsen / Åbne vinduer med god lydisolation 42

42 8. Window Type 2: Standard Window with internal solution Illustration 8A. Prototype solution for "regular window" with internal solution. This chapter describes a "common window" with an internal solution, the main purpose being to improve a standard Windows sound insulation without adding anything to the windows outside. The design principle focuses on openable windowsr with moderate sound isolation in open mode, ie. A window that can be used in areas where noise is about 5 db above the limit value. Unlike many air supply windows, which often requires a special windows format and upside down respectively up and down, and shutter solutions that affect the design and appearance of the exterior facade, the idea is to be able to use common windows formats with ordinary open functions (as side-hung or double-hung) combined with an inner sound shielding in windows. The idea is therefore to work with a cheaper solution (than russer windows) that fits in a more common size window hole (here a width x height of 1250 mm x 1500 mm). The reference is therefore a single two-fold window as shown in Figure 8B. Miljøstyrelsen / Åbne windowr with god lydisolation 42

43 Illustration 8B. Photos of the reference window: Single double-glazed window shown here from both the inside side (left foot) and the outside side (right photo). 8.1 Developing a solution principle The principle could be that in a traditional double window structure between the two windows, an audio shield can be established that only appears when the windows is opened. The audio shield must ensure that there is a detour that reduces the direct audio transmission while there is some sound absorption in the cavity. For example, when the windows is closed, the "sound coded" is folded up and parked in the frame or rolled up at the top of the windows so that there is free viewing through this. The "sound cushion" will in part, however, partially close the light incident / view. Two solutions are based. The one solution focuses on a two-sided side-hung window with two frames (hereinafter referred to as "two-wing"), while the other focuses on a one-sided side-hung window with one frame (hereinafter referred to as "side-hung"). Miljøstyrelsen / Åbne windowr with god lydisolation 43

44 Illustration 8C. Photo of the closed two-sided window set from the inside.. A basic windscreen structure has been built that can be used for both solutions, depending on the frames that are opened. The construction consists of 2x2 frames that are assembled as shown in the illustration in Illustration 8D (right side) - see other photos in Illustration 8C and Illustration 8D (left side). In the case of the two-sided window, the setup is as the left picture in Illustration 8D Illustration 8D. Photos of windows in open state. The left photo shows windows opened as a two-wing window while the right photo shows all the openings open. Miljøstyrelsen / Åbne windowr with god lydisolation 44

45 Illustration 8E. Sketch of the structure of the twisted window (see Illustration 8F for section through the same sketch). Exterior open frame Center plate Two-piece plate Interior open frame Interior frame Illustration 8F. Horizontal section through sketch showing the twisted setup (see Illustration 8E). Miljøstyrelsen / Åbne windowr with god lydisolation 45

46 Illustrations 8E and 8F show a sketch of the two-speed setup. The double-glazed window is divided in the center of a center plate on which the transverse plate is mounted. Both center plate and transverse plate are for mockup measurements made of plywood. During the measurements, absorbents are placed on the center plate, on the transverse plate and in the frame (both side, top and bottom). Similarly, the sketches in Illustration 8G and 8H show how the side-hung window is built (It is not a "real" one-sided side-hinged window, but it is expected that the results measured with this construction will be very close to a real one-sided side-hung window Since the narrower angle that will be in a "correct" side-hung solution will be irrelevant to the silencing conditions). The illustrations outline how a sound absorbing element (here as a transverse plate) is integrated into the cavity between the two windows. Measurements are made where the transverse plate has different lengths and different absorbent capabilities. Both measurements are made that meet the requirement for a flow area 0.35 m2 and measurements where the opening area is 0.35 m2 but where the flow area at the smallest point is smaller. In the final version of windows for both two-sided and side-hanging solution, it is thought that the transverse plate should be able to be driven / rolled away, so that there is still the possibility of full light incident with closed windows, such as a folding plate of absorbent material. Another possibility is that the board is made of transparent material, avoiding complicated solutions such as a folding plate and ensuring transparency. For construction of respectively. The transverse plates as well as the "middle plate" have been used for ordinary chipboard. As an absorbent material, SUND Environmental Undertaking is used with a thickness of 20 mm. In some cases (on the side of the inside of the frame by the twisted structure) a thickness of 40 mm has been used. For the covering of the frames, the same absorbent is used in 20 mm thickness. However, in some cases, it has been measured with an absorbent absorbent (absorbent used in the side of the bin - opposite the transverse plate) of 40 mm in thickness in the twisted con FIGUREation. Miljøstyrelsen / Åbne windowr with god lydisolation 46

47 Illustration 8G. Sketch of the construction of the side-hung window (see Illustration 8I for section through the same sketch). Exterior open frame Two-piece plate Exterior closed frame Incidence side Interior open frame Interior closed frame Illustration 8H. Horizontal section through sketch showing the side-hanging test setup (see Illustration 8H). Miljøstyrelsen / Åbne windowr with god lydisolation 47

48 8.2 Laboratory measurements on mockup solution Subsequently, a number of laboratory measurements have been performed on mockup solutions Excessive solution Illustration 8I. Image of two-winged solution during measurements. Absorbents can be seen on the center plate and in the body (both side and bottom), but not on the transverse plate. First, the soundproofing of the closed double windrow and the effect of the center plate and the addition of the absorbent are investigated. Referring to FIGURE 15, the closed configurations are generally followed in the frequency range Hz. It is also seen that the configurations without plate mounted at the cross are closely monitored at the lowest frequencies. For high frequencies, greater damping is obtained due to the 20 mm SUND mounted in the frame. The last configuration where the center plate is mounted at the cross has a generally higher sound insulation. This may be because the amount of absorbent is increased with the free surfaces of the now mounted center plate and the changed cavity. Miljøstyrelsen / Åbne windowr with god lydisolation 48

49 Noise Reduction [db] FIGURE 15. Closed windowr with different internal settings - always used 20 mm at absorbent. 80 ( M 2016 ) 70 ( M 2001 ) 60 ( M 2015 ) Frequency [Hz] Measurement no. R w R w+c tr Description (location and absorbers) [db] [db] M Without center plate and without absorbent M With center plate. Absorbent on center plate, in the frame and in the dropframe M Without center plate. Absorbent in the frame and in the collar With open windowr (opening area 0.35 m2), see Illustration 8I, it appears from FIGURE 16 that there is a significant improvement from the reference solution (a single window) to a double construction for an open window (0.35 m2). Rw + Ctr increases by 4-7 db depending on the composition of the double structure and addition of absorption. However, it should be noted that there is also a significant difference between the different double constructions in the spectrum. The difference occurs when a center plate is mounted at the groove. A dive will appear about 125 Hz with the center plate mounted. An immediate explanation of this difference is that the dimension of the cavity between the two window sections is changed. The wavelength of 125 Hz is approx m, giving a quarter length of 0.68 m. This length is very close to the distance between the center plate and the frame. This causes some frequencies to go through windows without much loss. Miljøstyrelsen / Åbne windowr with god lydisolation 49

50 Noise Reduction [db] In structures where the center plate is removed, it is seen that the marked dive disappears from the 125 Hz. On the other hand, a new dive, however, is almost as high as about 70 Hz. The wavelength for 70 Hz is approx. 4.9 m, giving a quarter length of 1.23 m. This distance fits well with the distance between the two frames. This again causes certain frequencies to pass windows without the big loss. FIGURE 16. The importance of the center plate and the comparison between the reference window, two-winged double window and side hung double window. The window is open 0.35 m 2 and the absorbent thickness is 20 mm. 60 ( M 2019 ) 50 ( M 2017 ) 40 ( M 2002 ) 30 ( M 2018 ) 20 ( M 2033 ) 10 0 Frequency [Hz] R w R w+c tr Description (location and absorbers) Measurem ent no. [db] [db] M Reference window / not double window M Two-winged. Without center plate. Without absorbents. M Two-winged. With midterplade. Absorbent on center plate, in frame and inlet M Two-winged. Without center plate. Absorbent in the frame and M incidence Sidehung Without center plate. Absorbent in the frame and incidence Miljøstyrelsen / Åbne windowr with god lydisolation 50

51 There is in this part of the project does not work with removing the dip at 125 Hz. Accordingly, all the measurements with the cross mounted will contain the dive to a greater or lesser degree. For the final construction with the central plate mounted at the glazing bars, a perforated solution envisioned. This solution must utilize the cavity in the closed part of the double-glazed window. The perforation rate of the plate must be adjusted to 125 Hz, so that this frequency is judged extraordinarily. This construction will most likely imply that the transverse plate is to be mounted. Thus, with a perforated center plate, a folding plate / roller blind or the like can not be used. FIGURE 17 to FIGURE 19 compares different constructions in the cavity of the two-winged window. The constructions comprise different lengths of the transverse plate from cm from the center plate, where the opening area is maintained to 0.35 m 2 and with different set-ups of absorbent in the cavity. Miljøstyrelsen / Åbne windowr with god lydisolation 51

52 Noise Reduction, R [db] For the transverse plate with a length of 35 cm the rule of 0.35 m 2 as the minimum crosssectional area is not observed. To achieve a satisfactory cross-sectional area, the "outer" opening area of the windows itself must be at least 0.64 m 2. Measurements have been performed with both cone FIGURES, both with and without compliance with the 0.35 m 2 for the flow area. In FIGURE 17 to FIGURE 19, the determining opening area is defined as the area between the transverse plate and the frame. Accordingly, for the plate of 35 cm there will be a smaller flow area, mentioned above FIGURE 17. The meaning of the transverse plate with reference to a single window. The center plate is used (except for reference) and there is a 20 mm absorbent on the center plate, cross-sectional plate, in the frame and in the inlet. The opening area is 0.35 m ( M 2019 ) 50 ( M 2002 ) 40 ( M 2014 ) 30 ( M 2010 ) 20 ( M 2007 ) 10 0 Frequency [Hz] Measurement no. R w R w+c tr Description (location and absorbers) [db] [db] M Reference window (not double window) M Without plate M Transverse plate with length20 cm M Transverse plate with length29 cm M Transverse plate with length35 cm Miljøstyrelsen / Åbne windowr with god lydisolation 52

53 Noise Reduction, R [db] In FIGURE. 17 and FIGURE 18, the different sheet lengths are shown respectively. With and without absorbent on the transverse plate. The value for Rw + Ctr is based on double constructions without transverse plate (but with center plate) mounted 11 db. In both cases, the variation of the transverse length of the plate is seen to have a small influence on the Rw value, but on Rw + Ctr there is no variation between the values, regardless of whether a long or short transverse plate has been measured. Values are stable for all 2x3 measurements (M 2014, M 2010, M 2007, M2013, M2009 and M2008) with varying lengths of the transverse plate for. In relation to the starting point of 11 db for Rw + Ctr, there is a modest increase of 1 db per. initiatives. It gives an Rw + Ctr on respectively. 12 db with a raw chipboard mounted and 13 db with 20 mm SUND on both sides of the particle board. FIGURE 18. Meaning of transverse plate with reference to a single window. The middle plate is used (except for reference), and there is 20 mm absorbent in the frame and in the drop. The opening area is 0,35 m ( M 2019 ) 50 ( M 2002 ) 40 ( M 2013 ) 30 ( M 2009 ) 20 ( M 2008 ) 10 0 Frequency [Hz] Measurement no. R w R w+c tr Description (location and absorbers) [db] [db] M Reference window / not double window M Without plate M Plate with length20 cm M Plate with length29 cm M Plate with length35 cm Miljøstyrelsen / Åbne windowr with god lydisolation 53

54 Noise Reduction, R [db] In FIGURE 19, the length of the transverse plate is maintained while the position of the absorbents and the thickness thereof are varied. The transverse plate has a fixed length of 29 cm, the opening area is 0.35 m 2, so that the flow area is at least 0.35 m 2 throughout the windows. The 29 cm are chosen as this length can precisely meet the requirements set. They are compared respectively. With and without absorbent on the transverse plate as well as varying thickness of the absorbent at the drop-in. As mentioned above, there are modest changes in Rw + Ctr obtained by mounting a transverse plate (Rw + Ctr is unchanged at 12 and 13 db, respectively, without and with absorbent on the plate). In the case where a thicker absorbent is fitted In addition, a slight increase is obtained, so that Rw + Ctr is respectively. 13 and 14 db without and with absorbent on the transverse plate. FIGURE 19. Meaning of the influence of various absorbent configurations at a length of 29 cm for the transverse plate. The opening area is 0.35 m ( M 2019 ) 50 ( M 2002 ) 40 ( M 2009 ) 30 ( M 2010 ) 20 ( M 2011 ) 10 ( M 2012 ) 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M Reference window / not double window M Without plate M Without the absorbent sheet and the absorbent 20 mm in the frame of M incidence With the absorbent sheet and the absorbent 20 mm in the frame of M incidence With the absorbent sheet and the absorbent 40 mm in the frame of M incidence Without the absorbent sheet and the absorbent 40 mm in the frame of incidence Miljøstyrelsen / Åbne windowr with god lydisolation 54

55 In FIGURE 20, the sound insulation is shown for different opening areas as well as different lengths of the transverse plate. It has been tested with a cross-sectional plate of 46 cm, giving an opening area of 0.20 m 2. This measurement is compared to the measurement made with a 29 cm plate, which is the largest allowable plate if the flow area of 0.35 m 2 is to be met. It can be seen that the transverse plate length combined with a smaller opening area has an effect that causes the single value of Rw + Ctr to rise by 2-3 db relative to the comparative measurement so that the final value becomes respectively. 14 and 16 db without and with absorbent. That the increase in sound insulation with absorbent for the transverse plate of 46 cm is greater than for shorter plates can be attributed to the total area covered with absorbent is somewhat larger. Miljøstyrelsen / Åbne windowr with god lydisolation 55

56 Noise Reduction, R [db] FIGURE 20. Comparison of measurement with 0.20 m 2 opening with and without absorbent and measuring with 0.35 m 2 opening with and without absorbent. For reference, the FIGURE without crossplate is open 0.35 m ( M 2002 ) 50 ( M 2003 ) 40 ( M 2004 ) 30 ( M 2009 ) 20 ( M 2010 ) 10 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M ,35 m 2. Without transverse plate M ,20 m 2. Transverse plate 46 cm, without absorbent on the plate M ,20 m 2. Transverse plate 46 cm, with absorbent on the plate M ,35 m 2. Transverse plate 29 cm, without absorbent on the plate M ,35 m 2. Transverse plate 29 cm, with absorbent on the plate lade 29 cm, with absorbent på pladen Miljøstyrelsen / Åbne windowr with god lydisolation 56

57 8.2.2 Two-winged solution summarised Different constructions of a two-winged window have been investigated. Relative to reference windows (a single window), a significant improvement is seen for an open window when installing an additional window portion to achieve a double structure with a void between the two window sections (improvement of the single-digit values of about 4 db for Rw + Ctr). The cavity (between the window sections) is furthermore modified with transverse plates in different lengths and with different configurations of absorbents. In compliance with a flow area of 0.35 m 2, an improvement of up to 4 db for Rw + Ctr (relative to double construction without center plate and absorption) is seen. It also appears that variation of the length of the transverse plate (which meets the flow area of 0.35 m 2 ) does not cause any change in sound insulation on the single-value values. Adding absorbent to the transverse sheets gives an improvement in sound insulation of approx. 1 db. Calculations have been made where the dive at the 125 Hz is neutralized, so that it follows the curve naturally. There is no change in the single-digit values for the measurements, even if the dive is removed. It can therefore be concluded that the results would not have been different if the dive was not existing Side hung solution Similarly, a measurement series has been performed on the simulated side-hung solution, see Illustration 8J. FIGURE 21 and FIGURE 22 show the importance of varying lengths of the transverse plate respectively. Without and with 20 mm absorbents on the transverse plate. In summary, it can be concluded that a longer cross-section provides a higher sound insulation especially for frequencies from 613 Hz and up, but as with the twisted window, the greatest improvement is achieved when switching from singlewindow to doublewindow. However, the addition of the cross-section also has an improvement - up to 2 db at the solution without absorbent on the crossboard and 3 db at the solution with transducer absorbent (for Rw + Ctr) - for lengths of the transverse plate up to 29 cm. In order to obtain a cross section of 0.35 m2, the length of the transverse plate may not exceed 29 cm. The target that is done with a plate of 51 cm, results in a flow area of 0.20 m 2. For the plates 60 and 70 cm long, the flow area is 0.15 m2. Sound insulation (Rw + Ctr) increases 3 and 2 db with and without absorbent when the opening area is cut down to 0.2 m 2 (51 cm plate). Sound insulation (Rw + Ctr) increases another 2 db without absorbent and 4 db with absorbent by extending the transverse plate from 51 cm to 70 cm. Miljøstyrelsen / Åbne windowr with god lydisolation 57

58 Illustration 8J. Photos of the simulated side-hung solution without absorbent on the crossplate. Miljøstyrelsen / Åbne windowr with god lydisolation 58

59 Noise Reduction, R [db] FIGURE 21. Comparison of different lengths of the transverse plate mounted in "side hinged" constitution without absorbent on the transverse plate. The opening area is 0.35 m ( M 2019 ) 50 ( M 2033 ) 40 ( M 2031 ) 30 ( M 2029 ) 20 ( M 2027 ) 10 ( M 2025 ) 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M Reference windows (single window) - (setup as two-winged) M Double window, without transverse plate M Double window, transverse plate 29 cm long M Double window, transverse plate 51 cm long (0,2 m 2 ) M Double window, transverse plate 60 cm long (0,15 m 2 ) M Double window, transverse plate 70 cm long (0,15 m 2 ) Miljøstyrelsen / Åbne windowr with god lydisolation 59

60 Noise Reduction, R [db] FIGURE 22. Comparison of different lengths of the transverse plate mounted in "side hung" could be considered with 20 mm absorbent on the transverse plate. The opening area is 0.35 m ( M 2019 ) 50 ( M 2033 ) 40 ( M 2032 ) 30 ( M 2030 ) 20 ( M 2028 ) 10 ( M 2026 ) 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M Reference windows (single window) - (setup as two-winged) M Double window, without transverse plate M Double window, transverse plate 29 cm long M Double window, transverse plate 51 cm long (0.2 m2)) M Double window, transverse plate 60 cm long (0.15 m2) M Double window, transverse plate 70 cm long (0.15 m2) In addition, the importance of the absorber's location is investigated by a length of the crossing plate of 70 cm (which gives a gap of 53 cm). The results are shown in FIGURE 23. It can be seen that the thickness of the deposition absorbent (absorbent used in the side of the frame - opposite the transverse plate, see Illustration 8H)) has a significance in the frequency range Hz, where a doubling of the thickness Of the absorbent has a clear improvement in the sound insulation. The addition of absorbent to the entire crossplate has a very clear improvement in sound insulation throughout the frequency range from Hz. With a transverse plate with a length of 70 cm, the increased area of the absorbent is also in the order of 2 m 2. Miljøstyrelsen / Åbne windowr with god lydisolation 60

61 Noise Reduction, R [db] FIGURE 23. Comparison of different considerations of absorbents, all with 70 cm crosssection (except for reference measurements). The opening area is 0.35 m ( M 2019 ) 50 ( M 2033 ) 40 ( M 2025 ) 30 ( M 2024 ) 20 ( M 2026 ) 10 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M Reference windows (single window) - (setup as two-winged) M Double window, without transverse plate M cm plate without absorbent. 20 mm absorbent insert M cm plate without absorbent. 40 mm absorbent insert M cm plade with absorbent. 20 mm absorbent insertt Side hung solution summarized Various constructions of a side-hung window have been investigated. Relatively to the reference window, a significant improvement is seen when installing an additional window part to achieve a double structure with a void between the two window sections (improvement of the single-digit values of about 4 db for Rw + Ctr). The cavity (between the windows) is also modified with transverse plates in different lengths and with different configurations of absorbents. With 0.35 m 2 flow throughput, an improvement of up to 3 db for Rw + Ctr (relative to double construction Without center plate and absorption) is seen. Contrary to the doubleglazed window, a clear sound insulation improvement is seen by extension of the transverse plate (which meets the flow area of 0.35 m 2 ). Miljøstyrelsen / Åbne windowr with god lydisolation 61

62 Greater improvement can be achieved by further extension of the transverse plate (flow area of 0.20 m 2 / 0.15 m 2 ). Adding absorbent to the transverse sheets gives an improvement in sound insulation of approx. 2-4 db (for Rw + Ctr). 8.3 Development of prototype Based on the measurements on the mockup solutions, it was decided to continue with the twofold solution. For the prototype, the crossplate is replaced by a glass panel that can be pushed back and forth, ie. Both allow the panel to slide all the way to create a large airflow and also allow the panel to completely slide. Drawings are shown in Figure 8K and Illumination 8L. However, the spacing between the windows is different from that shown so that the removable glass panel is located in the middle of the two windows, see photos in Illustration 8A, 8M and 8N. It is an aluminum construction. Windows is for practical reasons the prototype measurements mounted in a double gypsum board wall (as opposed to the mockup solutions mounted in a double concrete wall) as it allows for work with a deeper carmabsorbent, see Chapter 7. The spacing between the windows is the same as in the two-leaf mock-up solution. Illustration 8K. Horizontal section of the prototype resolution. Miljøstyrelsen / Åbne windowr with god lydisolation 62

63 Illustration 8L. Vertical section of the prototype resolution. Miljøstyrelsen / Åbne windowr with god lydisolation 63

64 8.4 Laboratory measurements on prototype Subsequently, a number of measurements have been made on the prototype model, as shown below. Illustration 8M. Photos of applied carmabsorbent. Left side: 20 mm SUND. Right side: Perforated plasterboard in front of mineral wool in the hole wall. Illustration 8N. Photos of applied frame absorbent. Left side: No absorbent (unbroken plasterboard). Right side: Open to applied mineral wool in the double plasterboard wall. Miljøstyrelsen / Åbne windowr with god lydisolation 64

65 Noise Reduction, R [db] FIGURE 24 shows the sound insulation of the prototype resolution in closed mode (the outer window r in the double structure) with the internal shooting window in different positions as well as with and without frame absorption (note that no correction for possible influence of flank transmission) is also compared with Correspondingly constructed mockup construction. Conversely, there is no big difference between the results except the frequency range over 1200 Hz, both the curves and the single-digit values are comparable. FIGURE 24. Meaning of different positions of the internal shooting window for closed windowsr both with and without frame absorber. In addition, compared to measurements made on a corresponding mockup structure without absorbent and center plate. 80 ( M 2101 ) 70 ( M 2102 ) 60 ( M 2103 ) 50 ( M 2016 ) Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M No frame absorbent. Sliding Window located 29 cm from the center M No frame absorbent. Sliding Window located 53 cm from the center M mm frame absorbent. Sliding Window located 29 cm from the M center Two-winged mockup. No center plate. No absorbent. Miljøstyrelsen / Åbne windowr with god lydisolation 65

66 Noise Reduction, R [db] In FIGURE 25, the prototype resolution sound insulation is shown in open state with the internal sliding window set so that 0.35 m 2 opening area and flow area are just met and with different variants of frame absorbents. Compared with a single window, the sound insulation improvement for low frequencies below 300 Hz is limited, whereas there is clearer improvement over 300 Hz. For single-digit values, the improvement is 6-9 for Rw and 5-7 db for Rw + Ctr. Compared with the measurement without frame absorbent (M 2106), the improvement in sound insulation is limited (Up to 3 db for Rw and up to2 db for R w+c tr), Where the best effect is achieved when open to the cavity insulation. FIGURE 25. Comparison of different variants of carmabsorbent at open window with sliding windows so that 0.35 m 2 opening area and flow area are just met. 60 ( M 2019 ) 50 ( M 2106 ) 40 ( M 2104 ) 30 ( M 2107 ) 20 ( M 2108 ) 10 0 Frequency [Hz] Measurem ent no. R w [db] R w+c tr [db] Description (location and absorbers) M Reference windows (single window) - (setup as two-winged) M Without frame absorbent M With 20 mm frame absorbent M Perforated plate (mineral wool behind it) in the frame of incidence M Fully opened up mineral wool behind the sill of incidence Miljøstyrelsen / Åbne windowr with god lydisolation 66

67 RNoise Reduction, R [db] For the mockup solution of the same structure (see section 0), it was found that variation of the length of the transverse plate (which meets the flow area of 0.35 m 2 ) did not cause any significant change in the sound insulation on the single-digit values. Variation of shooting windows is shown in FIGURE 26, where no particular change in sound isolation is seen on the single-digit values. FIGURE 26. Comparison of different positions of shooting windows where open to the insulation in the double plasterboard wall. 60 ( M 2108 ) 50 ( M 2109 ) Frequency [Hz] Measurement no. R w R w+c tr Description (location and absorbers) [db] [db] M Sliding Window located 29 cm from the center M Sliding Window located 46 cm from the center Miljøstyrelsen / Åbne windowr with god lydisolation 67

68 8.5 Conclusion The chapter describes a "common" window with an internal solution, the main purpose being to improve a standard Windows sound insulation without adding anything to windows outside. The design principle focuses on openable windowsr with moderate sound isolation in open mode, ie. A window that can be used in areas where noise is around 5 db above the limit value. As a reference, therefore, a single two-winged window is used as shown in Illusion 8B. There are first worked with mockup solutions in two different variants; A two-winged and a side-hung window, and subsequently a prototype variant of the two-winged solution has been constructed. Compared with a single two-winged window, a good improvement - in both closed and open mode - is added by adding an inside two-winged window to overall achieve a doubling structure where the improvement in open mode is in the order of 5-7 db for Rw + Ctr. The addition of a transverse plate within double windings also has a meaning (1 db for Rw + Ctr). Variation of the length of the plate does not seem to have a sound insulation effect for the two- Jede window. For the side-hung solution, the addition of a transverse board has a sound insulation improvement effect of up to 2 db for Rw + Ctr. The addition of absorbent material to the transverse plate has an improvement effect of about 1 db for the twisted solution and approx. 1 db for Rw + Ctr for the side hinged solution. Addition of carmabsorbents also has an improved effect depending on the design / location. The aim of the design was to increase the sound insulation approx. 5 db compared to a plain open window. For the solution, a Rw of 15 db and a Rw + Ctr of 12 db has been obtained, which is a total improvement for Rw of 8 db and for Rw + Ctr of 5 db compared to a common open window. Miljøstyrelsen / Åbne windowr with god lydisolation 68

69 9. Window type 3: Standard window with exterior solution Illustration 9A. Photo of prototype of "Common Window" with external solution. This chapter describes a "regular" window with an attached external solution. The idea is to work with a solution that could both be used in situations where a higher sound insulation is desired by applying a structure to its existing window (eg by renovation), but also for the purpose of building a new "usual" window dimensions. Important parameters are as before: - visibility - Acceptable sound insulation - Variation options 9.1 Development of the principle solution The inspiration for the solution principle comes from the literature search (see section 6.2.2) and partly from DELTA's existing experiences. In order to test the ideas, we are initially working with mockup models. Following a brainstorming session, it was decided to work with three mockup models - all built of plywood: A. A solution that covers the window and with two openings B. A solution that covers the window and with one opening C. A solution that sits next to the window and with one opening Miljøstyrelsen / Åbne vinduer med god lydisolation 69

70 9.2 Laboratory measurements on a mockup solution All mockup models were mounted outside of a "regular window", hereinafter referred to as the reference window. As in the previous chapter, "Standard Window" builds on a double-glazed window (HSHansen a / s) in the standard format (width x height) 1230 mm x 1480 mm. For practical reasons, the window was mounted in a double plasterboard wall. Depending on the mockup model, two different reference windows were used (a "regular window"): - A two-fold inward window hinged in the side frame (see left side in Illustration 9B) - A two-way outward window hinged in the pilot post (see right side in Figure 9B) Of absorbents, SUND is used. Absorbents are included in the opening area as it is assumed that the air can pass through them. Illustration 9B. Photos of the "regular windows" used. The left photo shows a two-wing inward window hinged in the side. Right photo shows a two-winged outward window that is hinged in the mullion. See also Appendix 2 for general details of laboratory measurements Mockup-solution A Mockup solution A is in principle an open plywood box that is open at both ends, so the combined opening area at both ends meets 0.35 m 2. The structure is generally the same as at Folehaven [16] [17], but with modified geometry and with the possibility of investigating the importance of the location of additional absorbents. Miljøstyrelsen / Åbne vinduer med god lydisolation 70

71 The Mockup solution is here constructed as a fixed plywood box for practical reasons, but a possible pre-developed model is thought to be built partially (or entirely) of glass, so - as a minimum - The section covering the reference window is transparent and ensures visibility. The principle is shown in Illustration 9C. In addition, the finished model is built up, for example, as in Folehaven so that the entire external structure can be moved to one side, or it can be divided in the middle and thus is pushed to either side. Alternatively, it can all be built as a solid construction. If continued with the solution, it is DELTA's recommendation that the window can be opened more than 0.35 m 2. The reference of the mock-up solution A is a two-winged window inward in the standard format with one wing opened 0.35 m 2 (window wings opens towards the center), see Illustrative 9B. Illustration 9C. Principal Diagram of Mockup Solution A. Both the blue surface and the surfaces marked with plywood in two shades are constructed of the same type of plywood during the measurements. The blue surface here marks the part that is thought to be transparent (glass) in any prototype and is therefore not covered by absorbent material during the measurements. Both the light and dark part of the plywood (as well as the wall parallel to) can be covered by absorbent material. The bright part marks the default design, and the dark part marks the extension that was also examined. The actual mockup solution is shown in Figure 9D, where the design can be seen both inside and outside as well as with and without added absorption and with the two lengths of the solution being investigated. The dimensions of the default mockup solution are (width x height x depth) approx mm x 1640 mm x 160 mm. The extended mockup solution is extended 20 cm at both ends, ie. The overall dimension is 2250 mm x 1640 mm x 160 mm. After this, a series of measurements have been performed where selected comparisons of the sound reduction in 1/3 octave bands are shown in curve form together with the single-value values Rw and Rw + Ctr. The individual 1/3 octave band values as well as all relevant single-digit values can be found in Appendix 3. Miljøstyrelsen / Åbne vinduer med god lydisolation 71

72 Illustration 9D. Photos of the current implementation of mockup solution A. The left photo shows the extended version of mockup solution A set from the outside without fiberglass. The middle photo is taken into one end and shows the construction without added absorption material. The right photo is also taken into one end of the construction and shows that 20 mm absorption is added to the sides and 40 mm in the top and bottom. The Mockup solution is structured completely symmetrical, and therefore it should be irrelevant which of the two windows in the two-speed reference window that opens. Nevertheless, comparative measurements are performed as well as a measurement where both wings are opened so that the total opening- The area for all measurements is maintained at 0.35 m 2. The results can be seen in FIGURE 27, which shows that the curves are almost identical. The biggest difference is seen as expected by the measurement where both wings are opened. The single-digit values show the same result for all three measurements. Miljøstyrelsen / Åbne vinduer med god lydisolation 72

73 Noise reduction, R [db] FIGURE 27. Mockup Solution A - Not Extended. Investigation of the importance of which window is opened (total opening area always 0.35 m 2 - absorption not added). 60 ( M 3001 ) 50 ( M 3002 ) 40 ( M 3005 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M Right window open M Left window open M Both windows open Subsequently, the importance of addition of absorption is investigated, as can be seen in FIGURE 28. As expected, it can be seen that the sound insulation increases, the more absorption is added, especially for the highest frequencies. At the low frequencies, however, a noticeable effect is first seen by adding the 40 mm thick absorbent on the sides. The singledigit values show an improvement of 5-8 db (from 11 to 19 db for Rw and 10 to 15 db for Rw + Ctr). Miljøstyrelsen / Åbne vinduer med god lydisolation 73

74 Noise Reduction, R [db] FIGURE 28. Mockup Solution A - Not Extended. Significance of addition of absorption. 60 ( M 3020 ) 50 ( M 3017 ) 40 ( M 3018 ) 30 ( M 3019 ) 20 ( M 3020 ) 10 0 Measru ment n w [db] M M M M R w+c tr [db] Frequency [Hz] Description (location and absorbers) Without absorbents 40 mm in the top and bottom 40 mm in the top and bottom. 20 mm in the side 40 mm in the top and bottom. 40 mm in the side It is then interesting to look at the importance of prolonging the "box", as seen in FIGURE 29. The box is extended 20 cm at both ends. It can be seen that without absorbent the prolongation makes almost no difference - the curves are almost identical - however, there is a slight improvement in the low frequencies. With absorbents, there is an average improvement of approx. 3 db on both the curves and single-digit values. Miljøstyrelsen / Åbne vinduer med god lydisolation 74

75 Noise Reduction, R [db] FIGURE 29. Mock-up Solution A. Explanation of extended "box. 60 ( M 3020 ) 50 ( M 3019 ) 40 ( M 3011 ) 30 ( M 3016 ) Frequency [Hz] R w [db] R w+c tr [db] Description (location and absorbers) M M M M Not extended. Without absorbents Not extended. 40 mm absorbent in top, bottom and sides Extended. Without absorbents Extended. 40 mm absorbent in top, bottom and sides With the extended "box" it is also investigated whether the location of the absorbents is significant, see FIGURE 30. For three of the curves, the amount of absorption is identical (M 3013, M3014 and M 3015), but the location is very different. As can be seen, the curves are Almost identical up to about 1250 Hz, then the similarity ends. Of these three, the poorest absorbent placement is on the wall next to the windows. The clearest solution is to distribute the absorbent material on both sides to achieve the highest possible surface. However, it does not matter for the single-digit values (presumably since the difference is almost exclusively found over 2000 Hz). The very best result is achieved with 40 mm absorbent on both sides, which provides an improvement at almost all frequencies compared with the other configurations. For the single-digit values, an improvement of 3-4 db for Rw and 2-3 db for Rw + Ctr is achieved. Miljøstyrelsen / Åbne vinduer med god lydisolation 75

76 Noise Reduction, R [db] FIGURE 30. Mockup Solution A - Extended. Importance of placement of absorbent in sides (40 mm absorbent in top and bottom for all measurements). 60 ( M 3012 ) 50 ( M 3013 ) 40 ( M 3014 ) 30 ( M 3015 ) M 3016 ) 20 ( 10 0 Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M Without absorbent in the side M mm in both sides M mm in the side facing the inner side M mm in the side facing the outer side M mm in both sides Finally, measurements are compared to selected measurement results from Folehaven [17], as shown in FIGURE 31 (named SBi measurements 9 and 10). The assumptions are not 100% identical, yet a fairly good match between the curves is achieved. SBi measurement 9 was performed with only the original absorbent in the sound loop, while for SBi measurement 10, additional 40 mm SUND absorbent was added in the center of the audio loop. The opening area was adjusted to 0.35 m 2. Miljøstyrelsen / Åbne vinduer med god lydisolation 76

77 Noise Reduction, R / R' [db] FIGURE 31. Mockup Solution A Compared to Audio Encoding Metrics - Folehaven. 60 ( M 3018 ) 50 ( M 5007 ) 40 ( M 5008 ) Frequency [Hz] Measuremen R w / no. R[dB] M M M R w+c tr / R [db] +C Description (location and absorbers) Mockup solution A. 40 mm top and bottom. 20 mm in the sider. S Bi-measurement 9. No extra absorbent. Bi-measurement mm extra absorbent in the middle. Miljøstyrelsen / Åbne vinduer med god lydisolation 77

78 9.2.2 Mockup-solution B Mockup Solution B is similar to the overall mockup solution A with the important difference that the chipboard "box" is only open at one end opposite the wing in the reference window that opens. Since the "box" is only open at one end, the box must also be twice as thick as mockup solution A in order to have a sufficient opening area, see the principle diagram in Figure 9E. The Mockup solution is as with mockup solution A built into particle board, see Illustration 9F, but it is thought that - as a minimum - the field in front of the reference window in a final version is transparent. Therefore, no measurements with extra absorbent material have been performed on the part that is thought to be transparent - a principle outline of this is shown in Figure 9E, where the blue transparent section shows where the location of a pan is intended in a final solution. In addition, measurements have been made where the "box" is extended, which in Figure 9E is marked with a slightly darker color. Only the opening end of the extension is extended. On the "non-prolonged" part of the mockup solution was applied fiberglass plates to ensure sufficient weight and sound insulation, see Illustration 9F. It is here that the solution is open to the side, although similar results are expected if the opening is placed at the top or bottom (depending on the open window design of the window). The reference for mockup solution B is an inbound as with mockup solution A. Flared window in standard format with one wing opened 0.35 m 2 and with side hinged inward frames, see Illustration 9B (left photo). The dimensions of the default mockup solution are (width x height x depth) approx mm x 1640 mm x 290 mm. The extended mockup solution is extended 20 cm at one end, ie. The total dimensions are 2050 mm x 1640 mm x 160 mm. Illustration 9E. Principal sketch of mockup solution B. Both the blue surface and the surfaces marked with chipboard in two shades are constructed of the same type of particleboard during the measurements. The blue surface here marks the part which in a final solution is thought to be transparent (glass) and therefore is not covered by absorbent material during the measurements. Both the light and dark part of the plywood (as well as the wall parallel to) can be covered by absorbent material. The bright part marks the default structure and the dark part marks the extension that was also examined. Miljøstyrelsen / Åbne vinduer med god lydisolation 78

79 Illustration 9F. Photo of the current implementation of mockup solution B seen from the outside. Miljøstyrelsen / Åbne vinduer med god lydisolation 79

80 Illustration 9G. Two photos of mockup solution B, both taken from the open end of the construction. Left photo shows the construction without added absorbent; Right photo shows the maximum added amount of absorption, ie. 40 mm in top, bottom and sides and 20 mm in "middle". Results of measurements on the non-prolonged version with different degrees of addition of absorption are shown in FIGURE 32. The location of absorption is shown in both Figures 9G and 9I. As expected, it can be seen that increasing amount of absorption gives a higher sound insulation - however, it is primarily seen as an effect at the higher frequencies. An interesting result is also that the two measurements without absorption in the "end room" (M 3102 and M 3103) have a markedly different curve course than the measurements with absorption in the "end room" - however, the primary differences in the curve course are seen for the lowest frequencies. The "end room" is the closed end of the structure opposite the opening, see Illustration 9H and Illustration 9I. The shown addition of absorption gives an improvement on single-digit values up to 9 db for Rw and 6 db for Rw + Ctr. Miljøstyrelsen / Åbne vinduer med god lydisolation 80

81 U shaped absorber- 40 mm Mockup solution C Particleboard Silencing 40mm in the layer 40mm in the bottom 20mm in the middle Double plasterboard wall Illustration 9H. Horizontal sectional sketch seen from the inside, showing the solution with 40 mm U-shaped absorbent in the "end room", 40 mm absorbent at the bottom and 40 mm in sides and 20 mm absorbent in the center. 3x100 mm mineral wool + 40 mm absorbent Silencing Right frame Left frame 40 mm absorbent on the inside frame Illustration 9I. Horizontal sectional view, from the inside, shows the solution with 40 mm absorbent on the inside frame, 3x100 mm + 40 mm absorbent in the "endroom", 40 mm absorbent at the bottom and 40 mm in sides and 20 mm absorbent in the middle. Miljøstyrelsen / Åbne vinduer med god lydisolation 81

82 Noise Reduction, R [db] FIGURE 32. Mockup Solution B. Examination of Importance of Addition 60 ( M 3102 ) 50 ( M 3103 ) 40 ( M 3105 ) 30 ( M 3106 ) 20 ( M 3107 ) 10 ( M 3108 ) 0 Frequency [Hz] [db] [db] M M M M M M Description (location and absorbers) Without absorbents 40 mm in the top and bottom 40 mm In top and bottom. 3x mm in "end area" 40 mm In top and bottom. 3x mm in "end area". 20 mm in sides 40 mm In top and bottom. 3x mm in "end area"40 mm in sides 40 mm In top and bottom. 3x mm in "end area"40 mm in sides. 20 mm i middle. The significance of which of the frames in the two-wave reference window is opened is illustrated in FIGURE 33. The measurements are performed based on 40 mm absorption in the top and bottom and 40 mm in the sides of the mockup solution opening - the loop and 20 mm in the middle of the audio, see Illustration 9I. If the right frame is opened instead of the left, it significantly improves sound insulation for the lowest frequencies below 125 Hz. For frequencies above 125 Hz, the best sound insulation with the left frame is open. On the single-digit values, the left frame provides an improvement of 4 db for Rw and 2 db for Rw + Ctr relative to the right frame. In the same FIGURE, an equally effective effect of adding 40 mm absorption inside the bin is also examined opposite the open frame in the reference window, see Figure 9I. As can be seen, the difference is insignificant. Miljøstyrelsen / Åbne vinduer med god lydisolation 82

83 Noise Reduction, R [db] FIGURE 33. Mockup Solution B. Meaning of which window opens on the basis of 40 mm absorbent in top, bottom and sides, and 20 mm absorbent in the middle. 60 ( M 3108 ) 50 ( M 3109 ) 40 ( M 3110 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M x100 mm + 40 mm in "end area". Left frame open. M x100 mm + 40 mm In "end room" and 40 mm on the inside frame. Left frame open. M x100 mm + 40 mm in "end room". Right frame open The meaning of the "end room" is then desired to be illuminated - ie. The amount and location of absorption in the closed part of the box opposite the opening, see Figures 9G and 9I. Selected results are shown in FIGURE 34. The three displayed measurements yield relatively comparable results with db single-value Rw and db for Rw + Ctr, although the overflow area of the absorbents, thickness and volume are quite different, See the table below. Miljøstyrelsen / Åbne vinduer med god lydisolation 83

84 Noise Reduction, R [db] R w R w+c tr surface area Thickness Volume [db] [db] [m 2 ] [m] [m 3 ] M ,40 0,34 0,14 M ,40 0,14 0,06 M ,22 0,04 0,05 The reduction curves for the three solutions vary somewhat - primarily in the frequency range Hz. FIGURE 34. Mockup Solution B. Examination of Type and Location of Absorbent in "End Room" Based on 40 mm absorbent at the top, bottom and sides, and 20 mm absorbent in the center. 60 ( M 3108 ) 50 ( M 3111 ) 40 ( M 3112 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M x100 mm + 40 mm i end room M x100 mm + 40 mm i end room M U shaped bottom of 40 mm absorbent Miljøstyrelsen / Åbne vinduer med god lydisolation 84

85 Noise Reduction, R [db] Subsequently, the mockup solution is extended. The results from these measurements are shown in FIGURE 35, where the "box" is extended 20 cm at the end where the opening is, see the principle diagram in Illustrator 9E. FIGURE 35 shows three measurements where measurement M 3115 is the result of placing 13 mm gypsum board in front of the "end space" (filled with absorption), thus illuminating a total less amount of absorption in the mockup solution. The other two measurements shown in FIGURE are with the U-bottom in the "end room". As compared to the three measurements, as added previously, add-on absorption gives a higher sound insulation, here for most frequencies, but also for single-value values that increase 1-2 db for Rw and 2-3 db for Rw + Ctr. FIGURE 35. Mockup Solution B - The box is extended 20 cm. 60 ( M 3113 ) 50 ( M 3114 ) 40 ( M 3115 ) Frequency [Hz] [db] [db] M mm In top, bottom and sides. U-bottom of 40 mm absorbent M mm in top, bottom and sides. 20 mm in the middle. U-bottom of 40 mm absorber. M mm In top, bottom and sides. 20 mm in the middle. 3x100 mm + 40 mm in "end room" with 13 mm gypsum board in front. Miljøstyrelsen / Åbne vinduer med god lydisolation 85

86 Noise Reduction, R [db] Finally, the non-prolonged version and the extended version are compared. The result of this is shown in FIGURE 36. It can be seen that the extension has only a positive effect on sound insulation that has been improved throughout the frequency range. On the single-digit values, an improvement of 3 db for Rw and 2 db for Rw + Ctr is seen. FIGURE 36. Mockup solution B. Comparison between non-prolonged and extended box, both with 40 mm absorbent at the top, bottom and sides and 20 mm in the middle. U-bottom of 40 mm absorbent in the "end room". 60 ( M 3112 ) 50 ( M 3114 ) Frequency [Hz] Measurement no.. R w R w+c tr Description (location and absorbers) [db] [db] M Non-extended M Extended Mockup-solution C The reference for mockup solution C is an outgoing two-winged window in the standard format with the frames hinged in the solder post with one frame opened 0.35 m2, see Illustration 9J. As with the two previous mockup models, mockup solution C is built into plywood, and here too the model Seen as a box open at both ends. The primary difference, however, is that the box is not located "above" the reference window, but instead next to it. Miljøstyrelsen / Åbne vinduer med god lydisolation 86

87 The solution is structured such that the frame is opened outwards and locked in one position to create a closed channel through the mockup model and through the window. The principle is shown on Illustrators 9J, 9K and 9L. Measurements are carried out with the "box" in two lengths and with added absorbent material on the sides. As in previous work packages, the importance of adding absorption and extending the "box" was primarily investigated. The dimensions of the part of the default mockup solution that is located to the right of the window element is (width x height x depth) approx. 470 mm x 1480 mm x 290 mm, see Illustration 9K and Illustration 9L. The extended mockup solution is extended 50 cm at one end, ie. The overall dimensions are 970 mm x 1480 mm x 290 mm. Illustration 9J. Principle sketch of mockup solution C. The mockup solution is shown here with two brown colors, in which the bright part marks the default structure and the dark part marks the extension that was also investigated. Both the light and dark part of the mockup solution (as well as the wall parallel to) can be covered by absorbent material. Miljøstyrelsen / Åbne vinduer med god lydisolation 87

88 Plywood covered with fiberglass Uncovered Plywood Illustration 9K. Two photos of mockup solution C. The left photo shows the structure seen from the outside side and shows the extended box (the default length of the box corresponds to where the fiberglass is attached (left side) and the addition is where the plywood plate is visible (right side ). The right photo shows the structure seen from the open end with the maximum added amount of absorption, ie 40 mm in the top, bottom and sides, and 20 mm in the "center". Illustration 9L. Principle sketch of mockup solution C seen from the inside. Absorption was applied to all parts shown here as plywood (brown colors) and on the inside side. Miljøstyrelsen / Åbne vinduer med god lydisolation 88

89 Noise Reduction, R [db] FIGURE 37. Mockup Solution C. Not Extended. 60 ( M 3204 ) 50 ( M 3205 ) 40 ( M 3207 ) 30 ( M 3206 ) 20 ( M 3208 ) 10 ( M 3209 ) ( M 3210 ) 0 Frequency [Hz] [db] [db] M Without absorbents M mm in top and bottom M mm in top and bottom. 20 mm in sides M mm in top and bottom. 40 mm in sides. M mm in top and bottom. 20 mm in sides. 20 mm in middle. M mm in top and bottom. 40 mm in sides. 20 mm in middle. M mm in top and bottom. 40 mm in sides. 20 mm in the middle. 20 mm at the window (see notation on Illustration 9L) F or mockup solution C in the non-extended version, selected results are shown in FIGURE 37. As with previous solutions, an improved sound insulation can be seen, the more absorption is added. Special absorption added to the pages has a good effect. However, the improved sound insulation is only for frequencies from 200 Hz and higher, while the frequency range below 200 Hz is almost unchanged regardless of the amount of absorption. However, in comparison to the mockup solution without absorbed, there is nevertheless improved sound insulation for the 9 db single Rw and 6 db Rw + Ctr for the best solution. Miljøstyrelsen / Åbne vinduer med god lydisolation 89

90 Noise Reduction, R [db] Similarly, selected results for mockup solution C in the extended version are shown in FIGURE 38. The same observations as in FIGURE 37 also apply here except that here an improvement is observed in sound insulation in the frequency range Hz by addition of absorption. Compared with the mockup solution without absorbent, here is an improved sound insulation for the 14 db for Rw and 10 db for Rw + Ctr for the best solution. FIGURE 38. Mockup Solution C. Extended. 60 ( M 3215 ) 50 ( M 3214 ) 40 ( M 3213 ) 30 ( M 3211 ) 20 ( M 3212 ) 10 0 Frequency [Hz] Description (location and thickness of absorbents) [db] [db] M M M M M Without absorbents 40 mm in top and bottom 40 mm in top and bottom. 20 mm in sides. 20 mm window 40 mm in top and bottom. 40 mm in sides. 20 mm wide 40 mm in top and bottom. 40 mm in sides. 20 mm in middle. 20 mm wide Mock-solution C in both the extended and non-extended version are compared in FIGURE 39, it can be seen that the length does not affect, in the absence of added absorption (no difference to its index values). However, the length is of great importance when added absorption (an improvement in sound insulation for the single-digit values of 5 db for Rw and 4 db for Rw + Ctr). Miljøstyrelsen / Åbne vinduer med god lydisolation 90

91 Noise Reduction, R [db] FIGURE 39. Mockup Solution C. Comparison with and without extension. 60 ( M 2019 ) 50 ( M 3204 ) 40 ( M 3215 ) 30 ( M 3209 ) 20 ( M 3212 ) 10 0 Frequency [Hz] Description (location and thickness of absorbents) [db] [db] M M M M M Reference (without mockup solution C) Without extension and without absorbent. With extension and without absorbent Without extension and with "full" absorbent (40 mm in top, bottom and sides. 20 mm in middle. 20 mm in diameter) With extension and with "full" absorbent (40 mm in top, bottom and sides. 20 mm in middle. 20 mm in diameter) A comparison of the three mockup solutions A number of experiments have been performed with each of the mockup solutions and selected results for the three mockup solutions are shown in FIGURES 40 and FIGURE 41. The former FIGURE shows results of the non-prolonged mockup solution and the latter FIGURE shows the results of the extended mockup solution. In each FIGURE, for each mockup solution, a measurement is also displayed without added absorption and the measurement with the most applied absorption. In addition, the measurement on the reference window is also included in both figures. Miljøstyrelsen / Åbne vinduer med god lydisolation 91

92 Noise Reduction, R [db] FIGURE 40. Comparison of standard mockup solutions. 60 ( M 2019 ) 50 ( M 3020 ) 40 ( M 3102 ) 30 ( M 3204 ) 20 ( M 3019 ) 10 ( M 3112 ) ( M 3210 ) 0 Frequency [Hz] Description (location and thickness of absorbents) [db] [db] M M M M M M M Reference (without mockup solution) Solution A. Without absorbent Solution B. Without absorbent Solution C. Without absorbent Solution A. With absorbent Solution B. With absorbent Solution C. With absorbent For the non-prolonged mockup solution, it can be seen in FIGURE 40 that it is mockup-solution B that has the best sound insulation - especially in the low frequency range - with or without absorbent. Mockup Solution A and C are approximately comparable. A similar picture can be seen for the extended mockup solutions in FIGURE 41. Mockup Solution C also looks to always have the lowest sound insulation without added absorbent while the absorbent solution is slightly better than mockup Solution A, see summary of single-digit values in Table 4. Miljøstyrelsen / Åbne vinduer med god lydisolation 92

93 No9ise Reduction, R [db] FIGURE 41. Comparison of extended mockup-solutions. 60 ( M 2019 ) 50 ( M 3011 ) 40 ( ikke målt ) 30 ( M 3215 ) 20 ( M 3016 ) 10 ( M 3114 ) ( M 3212 ) 0 Frequency [Hz] [db] [db] M M Ikke må - - M M M M Description (location and thickness of absorbents) Reference (without mockup-solution) Solution A. Without absorbent Solution B. Without absorbent Solution C. Without absorbent Solution A. With absorbent Solution B. With absorbent Solution C. With absorbent Tabel 4 Summary of single-digit values for the three mockup -Solutions Without absorbent With absorbent Standard Long Standard Long Standard Long Standard Long R w R w R w+c tr R w+c tr R w R w R w+c tr R w+c tr A B C Miljøstyrelsen / Åbne vinduer med god lydisolation 93

94 9.3 Development of prototype Based on the laboratory measurements performed, one design is selected for prototype development. Different factors weigh for and against each of the three mockup solutions. Solution A can be relatively quickly excluded, as a very similar design already exists as a finished product [16], and it is therefore more interesting to look at less tested constructions. The choice is primarily between Solution B and C. It is decided to work on solution C, although it is not this design that has given the best sound insulation, but on the other hand it is the most innovative and least tested Solution. In addition, it is also a smaller solution, does not have to be transparent and can thus be constructed in almost any material, however, with a density not less than 2 mm steel to ensure adequate sound insulation through the sides of the box (less density may Be sufficient, but this is not investigated in this project). The solution is also expected to be an interesting solution for architects and designers to work on. It is also one of the three Solutions that eases the opportunity to "fully open" with the possibility of venting with a Larger opening area than 0.35 m 2. A prototype version of the extended version of the Solution C model was therefore constructed (with the same dimensions). The model was constructed in 2 mm steel, and with grilles at each end. In comparison to the mockup measurements, the windows have also been replaced to 3 / 0.38 / mm argon-filled windows. Illustration 9M Photo from the outside of the prototype resolution. The left photo shows the structure slanting down from where the grille can be seen. Right-hand photo shows the structure seen from the prototype opening, where 20 mm absorbent is applied to the top, bottom and sides. See also Figure 9A. Miljøstyrelsen / Åbne vinduer med god lydisolation 94

95 Noise Reduction, R [db] 9.4 Laboratory measurements on prototype The prototype version of mockup-solution C is subsequently installed in the laboratory in the same way as mockup Solution C, and a number of laboratory measurements have been performed. FIGURE 42. Investigation of the importance of application of absorbents for the prototype. This is compared to the reference window and a closed window. 60 ( M 3316 ) 50 ( M 3303 ) 40 ( M 3309 ) 30 ( M 3304 ) 20 ( M 3305 ) 10 ( M 3301 ) 0 Frequency [Hz] Measurement no. R w R w+c tr Description [db] [db] M Open "regular windows" without prototype mounted. M Open, with prototype, without absorbents. M Open, with prototype and absorbents (40 mm in top and bottom. 20 mm in sides). M Open, with prototype and absorbent (40 mm in side). M Open, with prototype and absorbents (40 mm in top, bottom and sides) M Closed, with prototype, but without absorbents. Miljøstyrelsen / Åbne vinduer med god lydisolation 95

96 Selected results with the prototype are shown in FIGURE 42, where also the importance of applying absorbents is investigated. Compared with the reference window, sound insulation is not improved by application of the prototype alone, without addition of absorbent (for single values of the order of 3 db for Rw and 2 db for Rw + Ctr). By adding absorbents, the sound insulation is improved, however, primarily for frequencies above 250 Hz. The improvement with single-value absorbents is in the range of 8-11 db for Rw and 5-8 db for Rw + Ctr in relation to the measurement without absorbents. FIGURE 43 shows a comparison between: - Reference window only - Mockup Solution C in the extended version (ie, the same dimensions as the prototype solution) - both with and without added absorption - Prototype Resolution - with and without added absorption Both mockup-solution C and the prototype resolution without added absorption give almost identical results - there is very little difference between the curves and no difference in the single-value values. When compared to the measurement on the reference window, it can be seen that the sound insulation for mockup Solution C and the prototype is slightly higher than the reference window. The difference is primarily for frequencies above 300 Hz and is in the order of 3 db for Rw and 2 db for Rw + Ctr. Mockup Solution C and the prototype resolution added the same amount of absorption gives approximately the same single-digit values (22 and 21 for Rw and 18 and 17 for Rw + Ctr), but the curves are not quite the same as the sound insulation around 2500 Hz is higher for mockup -Solution C than for the prototype. Mockup Solution C and Prototype Resolution added absorption significantly higher sound insulation than the reference window, especially for frequencies over 500 Hz. Comparing the single-digit values is the difference in two-digit values (from 7 to db for Rw and from 7 to db for Rw + Ctr). Miljøstyrelsen / Åbne vinduer med god lydisolation 96

97 Noise Reduction, R [db] FIGURE 43. Comparison of mock-up Solution C in the extended version of the prototype invention - both applied to a "normal window" (two-winged, outward opening, with a frame-size 0.35 m 2). 60 ( M 3316 ) 50 ( M 3215 ) 40 ( M 3303 ) 30 ( M 3211 ) 20 ( M 3306 ) 10 0 Frequency [Hz] MeasuremeR w nt no.. [db] R w+c tr [db] Description M "Plain open window" without added mockup or prototype M Mockup-Solution C, extended, Without absorbents M Prototype, Without absorbents M Mockup-Solution C, extended, With absorbents (40 mm in top, bottom and sides. 20 mm v. rude) M Prototype, With absorbents (40 mm in top, bottom and sides. 20 mm wide) It was subsequently investigated whether the sound insulation of the prototype sheet material has a bearing. This was investigated by applying 3 mm bitumen plates inside the prototype structure. The results of this are shown in FIGURE 44, where it can be seen that the difference in sound insulation with and without bitumen is insignificant. Miljøstyrelsen / Åbne vinduer med god lydisolation 97

98 Noise Reduction, R [db] FIGURE 44. Investigation of the importance of the addition of bitumen on the side, bottom and top of the prototype. 60 ( M 3305 ) 50 ( M 3312 ) 40 ( M 3303 ) 30 ( M 3311 ) Frequency [Hz] Measurement no. R w R w+c tr Description [db] [db] M Without bitumen. 40 mm absorbent in the top, bottom and sides M With bitumen. 40 mm absorbent in top, bottom and sides M Without bitumen. Without absorbent M With bitumen. Without absorbent Miljøstyrelsen / Åbne vinduer med god lydisolation 98

99 9.5 Conclusion In this chapter, a two-fold "regular window" was examined with applied external soundproofing constructions to find a solution that could both be used in situations where you want a higher sound insulation by applying a design to its existing window (For example by renovation), but also for new construction to allow for the maintenance of "usual" window dimensions. Three variants of a "common window" with external solution have been investigated in mockup variants, after which one variant was selected and further developed into a prototype: A. A solution covers the window and has two openings (Mockup) B. A solution covers the window and has one opening (Mockup) C. A solution is located next to the window and has one opening (Mockup and prototype) For all solutions, freedom of view through the entire structure is straightforward, while view is obsolete to some extent. The Mockup solutions have all been studied in two different lengths to provide information about the variety options. A number of laboratory measurements have been performed on the four different constructions (three mockup solutions and a prototype solution), where an increased sound insulation of 4-15 db was obtained for the mockup solutions (described as single Rw + Ctr), depending on whether absorption was Added or not. For the prototype, an improvement for Rw + Ctr was obtained at 2-11 db depending on whether absorption was applied (compared to a single open window for both mockup solution and prototype solution). Miljøstyrelsen / Åbne vinduer med god lydisolation 99

100 10. Field Measurement Illustration 10A. Photo from the field measurements. Initially, the plan was to perform field measurements on each of the final constructions from work packages 1, 2 and 3 with the aim of assessing the sound effects of the constructs under realistic conditions, and ensuring that there are no significant systematic differences between laboratory results and field results. In order to do this, it was necessary to find locations with both the right opening hole (or possibility of adaptation), high level of traffic noise and lanes roughly parallel to building. It proved somewhat harder than expected. Therefore, it was decided to find a building with already installed Air supply windows, perform field measurements on the windows (preferably on several floors) and subsequently perform laboratory measurements on identical windows. The purpose of the measurements is to investigate whether there are significant systematic differences between laboratory results and field results, as well as an indication of whether the noise's approach is of importance. Miljøstyrelsen / Åbne vinduer med god lydisolation 100

101 Illustration 10B. Photo from the field measurements where the measurements on the second floor are under construction (the window is "fully open"). 3 microphones are located on the window. The task was therefore to find a building that, as far as possible, fulfills the following requirements: - The measurement can be performed according to DS / EN ISO : High noise level from traffic - Roadway approximately parallel to construction - Free view of the roadway from the window - 1-sheet air supply windows (ie, not a combined window containing both a spam window and a fixed portion) - Finished housing (ie a closed room behind the window) - One window per. room - Air supply windows that can be opened 0.35 m 2 - Air supply window produced by HSHansen a / s - Air supply windows mounted on several floors Østergade in Odense was selected as it meets the most important criteria. However, the windows could not be opened up to 0.35 m 2, and the view of the roadway is not entirely free, as there are single large trees (an avenue, see Illustration 10D). However, these criteria are less important for that Primary purpose. The properties on Østergade are all occupied, so the next step was gaining permission form residents to perform the field measurements. Not all occupants on the ground floor gave permission, and so the measurements were only performed on the first floor and the second floor. Miljøstyrelsen / Åbne vinduer med god lydisolation 101

102 Illustration 10C. Photo from the field measurements where the windows are opened as much as possible. The three microphones are attached to the window Performing Field Measurements The measurements were carried out over one day in August 2016, where there was low wind. The roadway was dry during the measurements. For each measurement at least 50 vehicles passed by. Five measurements were made: 1) 2nd floor with the window opened as much as possible 2) 2nd floor with the window closed 3) 1st floor with the window opened as much as possible 4) 1st floor with the window closed 5) 1st floor with the window opened approximately 4 cm When the windows are opened as much as possible, the outside window has an opening area of approximately 0.21 m 2, while the inside window has an opening area of approximately 0.24 m 2. It was also desired to perform measurements with a smaller opening degree. Inspired by the rules from Hamburg (see section ), it was chosen to open the windows 4 cm. The opening and closing of the winches is controlled by means of pushbuttons, and it is therefore not possible to control the closure of the outside and the inside of the window separately. The outside window is therefore opened approximately 4 cm, and that inside window is opened approximately 6 cm. This gives an outside opening area of approximately 0.03 m 2 and An interior opening area of approximately 0.07 m 2. Miljøstyrelsen / Åbne vinduer med god lydisolation 102

103 Distance from east to house Illustration 10D. Photo from the field measurements where the measurements were performed on the 1st floor. The openings are opened "4 cm". The measurements were performed as synchronous measurements with one indoor rotating microphone and three outdoor microphones located on the window, see Illustration 10C. The measurements were performed according to DS / EN ISO : 2016 [24]. Miljøstyrelsen / Åbne vinduer med god lydisolation 103

104 The outdoor noise level measured directly on the window (mainly from traffic on Østergade) was approximately LAeq = db during measurements. Unfortunately, the traffic noise level was not high enough for the closed windows measurements to be performed correctly (too little distance to background noise), and these measurements should therefore be used solely to verify the validity of the measurements with the window open. Horizontal distance from the curb to the building's façade was 6.7m at the window to the second floor and 7.3m at the first-floor window (the two windows are located in different trenches). The roadway was 10 m. There are approximately 16.5 m between the trees. The first floor (bottom) window was 3.3m above ground, while the window on the second floor (bottom) was 6.3m above ground, see Illustration 10C. The dimensions of the window are (width x height): 910 mm x 2155 mm. There is 32 cm between the windows of the inner part and the outer part. The room Behind the window has a volume of approximately 15 m 3 and was furnished in both cases - the reverberation time was measured and corrected for this. Absorbent material was used in the frame (inside the window) at the top and sides, while the bottom was not absorbent (20 mm SUND ) Results The result of the field measurements is shown in FIGUREE 45. The measurements with "fully open" windows make the distance to background noise sufficient, while the measurement with "4 cm" open windows is not sufficiently spaced for background noise in the frequency ranges Hz and Hz, and the values in these frequency ranges should therefore be seen as minimum values. Miljøstyrelsen / Åbne vinduer med god lydisolation 104

105 Noise Reduction, R' [db] FIGURE 45. Performed field measurements. Closed-up measurements have significant background noise problems and are included here only to give an idea of the importance of backlight noise. 60 ( M 4001 ) 50 ( M 4002 ) 40 ( M 4003 ) 30 ( M 4004 ) 20 ( M 4005 ) 10 0 Frequency [Hz] Measurem R w R w+c tr Description ent no nd floor. Opened outside 0.21 m 2 and inside 0.24 m M nd floor. Closed. M st floor. Opened outside 0.21 m 2 and inside 0.24 m 2. M floor. Closed. M st floor. Opened outside 0.03 m 2 and inside 0.07 m 2. For the "fully open" measurements, it can be seen that the curves at the upper frequencies (from 800 Hz) are approximately parallel for respectively. The measurements on the 1st and 2nd floor. For the middle frequencies ( Hz) the curves are relatively comparable, while the curves for the lowest frequencies (below 250 Hz) vary slightly in relation to each other. In general, sound insulation is highest for the measurement in the 1st-digit height, which can also be seen on the single-digit values, with a difference of 2 db for both Rw and Rw + Ctr. As expected, it can also be seen that the sound insulation is higher (4-5 db depending on whether it is Rw or Rw + Ctr) for the measurement where the openings are more closed (the opening area is smaller). This generally applies to the entire curve (except for the lowest frequencies), but is most pronounced for the highest frequencies. Miljøstyrelsen / Åbne vinduer med god lydisolation 105

106 10.2 Laboratory measurements The purpose of the laboratory measurements is, in principle, to mimic the field measurements in the laboratory. A copy of the windows from the field measurements has therefore been produced and a laboratory test wall has been constructed as a double plasterboard wall with the same thickness as the facade wall from the field measurements in which the window shutter is mounted. Subsequently a number of laboratory measurements have been performed, see Appendix 2. 21,5 cm 49 cm 38 cm Illustration 10E. Photo from laboratory measurements taken from inside. The openings are "completely open. In addition to the differences in situation (diffuse field versus free field), there are a number of other factors that are not the same: - Distance between outside opening vents and terrain / floor - Distance between the inside of the loft and the ceiling - Size of the rooms where measurements are made - Reverberation time in the rooms In the laboratory, on the outside side is 38 cm between the bottom of the window and the concrete floor ( m at the field measurements). On the inside of the laboratory is the wall mounted in one displaced opening, ie That there is 21.5 cm for a 17 cm deep concrete edge, while 49 cm is gathered from the top of the window, see Illustration 10E (the field measurements were about 47 cm between the top of the window and the ceiling). The interior of the laboratory is 50.7 m 3 (the room where there is measured by field measurements, is approximately 15 m 3 ). For both field measurements and laboratory measurements there are rigid for reverberation. Reverb time at field measurements is approximately 0.5 s, and the reverberation time at the laboratory measurements is approximately 1.6 s. Miljøstyrelsen / Åbne vinduer med god lydisolation 106

107 Illustration 10F. Photo from laboratory measurements taken from outside side. The left photo shows the openings "fully open" while the right photo shows the openings "4 cm" open Results of laboratory measurements in comparison with field measurements The results of the laboratory measurements are shown in FIGURE 46, where also the closedend results are shown as orientation. Flank transmission is not determined for the wall, and subjectively, there is a contribution from the surrounding wall, which is constructed as a double structure with three layers of plasterboard and a layer of fiberglass on each side. The closedend results should therefore be regarded as minimum values. For open openings, 2x2 measurements have been performed; i.e. Measurements for both openings used, as well as with and without 20 mm absorbent in the frame located at the top of the cavity between external and internal window construction. Miljøstyrelsen / Åbne vinduer med god lydisolation 107

108 Noise Reduction, R [db] FIGURE 46. Laboratory measurements performed in comparison with field measurements. 60 ( M 4101 ) 50 ( M 4102 ) 40 ( M 4103 ) 30 ( M 4104 ) 20 ( M 4105 ) 10 0 Frequency [Hz] M Closed. Without 20 mm absorbent at the top. M Opened outside 0.21 m 2 and inside 0.24 m 2. With 20 mm absorbent on the sides. Without 20 mm absorbent at the top M Opened outside 0.03 m 2 and inside 0.07 m 2. With 20 mm absorbent on the sides. Without 20 mm absorbent at the top M Opened outside 0.03 m 2 and inside 0.07 m 2. With 20 mm absorbent on the sides and top M Opened outside 0.21 m 2 and inside 0.24 m 2. With 20 mm absorbent on the sides and top The effect of adding absorbent to the top is only seen to have a fairly small effect, primarily in the frequency range over 200 Hz. For the single-digit values, the addition of absorbent at the peak gives an improvement of 1 db for Rw, whereas Rw + Ctr is unchanged. As expected, it can be seen that the smaller the opening area, the higher the sound insulation, which applies for almost all frequencies. For single-digit values, the limit in opening area means an improvement of 4 db for Rw, while Rw + Ctr increases 5 db. Miljøstyrelsen / Åbne vinduer med god lydisolation 108

109 Noise Reduction, R [db] Results of additional laboratory measurements FIGURE 47. Comparison of opening areas. All measurements with 20 mm absorbent at the top. 60 ( M 4104 ) 50 ( M 4105 ) 40 ( M 4108 ) 30 ( M 4109 ) Frequency [Hz] M Opened outside 0.03 m 2 and inside 0.07 m 2. M Opened outside 0.21 m 2 and inside 0.24 m 2 M Opened outside 0.35 m 2 and inside 0.37 m 2. (Opened as much as it is physically possible) M Opened outside 0.35 m 2 and inside 0.35 m 2 ("slanted position"). In addition to measurements comparable to the field measurements, measurements with an opening area of 0.35 m 2 were also performed. When openings open as much as physically possible, see photos in Illustration 10G and 10H, so the opening area is approximately 0.35 m 2. An opening area of 0.35 m 2 can also be found with the openings in an "sloping position", see also Illustration 10G and 10H. Both configurations are measured and shown in FIGURE 47 together with the two smaller opening areas from earlier. It can be seen that there is a clear difference between the two settings of 0.35 m 2 (about 1 db difference) and it can be concluded that the opening angle of the openings is at least as important as the opening area. Miljøstyrelsen / Åbne vinduer med god lydisolation 109

110 Illustration 10G. Photo from laboratory measurements taken from inside. Left photo shows opened open as much as possible while the right photo shows opened in an "inclined position". In both situations, the opening area is approximately 0.35 m 2. Illustration 10H. Photo from laboratory measurements taken from outside side. Left photo shows opened open as much as possible while the right photo shows opened in an "inclined position". In both situations, the opening area is approximately 0.35 m 2. Miljøstyrelsen / Åbne vinduer med god lydisolation 110

111 Noise Reduction, R [db] FIGURE 48. Investigation of the significance of the crack at the hinges. 60 ( M 4105 ) 50 ( M 4106 ) Frequency [Hz] M 4105 R24 R 19 +C Crevice of about 6 mm on the outside side and approximately 3 mm in the inside. M Slot closed with mineral wool and covered with adhesive tape At the top of the outer opening window and at the bottom of the inner bottom hinged window there is a small air gap that increases the more the window is opened, see Illustration 10I. Because a soundproofing effect is desired the fractures were therefore covered and the sound insulation measured. This was done by filling the cavity behind the crack with mineral wool and the crack was then covered with strips of canvas tape. FIGURE 48 shows the results of this comparison. As can be seen, there is only a small sound insulation significance of the crack. Miljøstyrelsen / Åbne vinduer med god lydisolation 111

112 Crack Illustration 10I. Photo from laboratory measurements taken from outside side. The photo shows a crack at the topof the window, which appears when opened Comparison of field measurements and laboratory measurements FIGURE 49 shows a comparison of field measurements and laboratory measurements where the openings are opened as much as it was possible to open them during field measurements. It can be seen that the sound insulation is highest for field measurements for frequencies below 250 Hz. In the other frequency range, the sound insulation is approximately comparable to a tendency for higher sound insulation for field measurements for frequencies above 800 Hz. For the single-digit values, the Rw values are also comparatively comparable (23-25 db for field measurements and db for laboratory measurements), while there is a somewhat greater difference for the Rw + Ctr values (21-23 db for field measurements and 19 db for laboratory measurements). Miljøstyrelsen / Åbne vinduer med god lydisolation 112

113 Noise Reduction, R / R' [db] FIGURE 49. Comparison of field measurement and laboratory measurements. All opened "fully open" (Exceptional opening area of 0.21 m2 and internal opening area of 0.24 m2). 60 ( M 4001 ) 50 ( M 4003 ) 40 ( M 4102 ) 30 ( M 4105 ) Frequency [Hz] Measurement no.. R w / R w R w+c tr / R w+c tr Description M Field Measurement. 2nd floor. M Field Measurement. 1st floor M Laboratory measurement. Without 20 mm absorbent at the top. M Laboratory measurement. With 20 mm absorbent at the top FIGURE 50 shows a comparison of field measurements and laboratory measurements with the openings opened approximately 4 cm. It can be seen that the sound insulation is highest for field measurements for frequencies below 250 Hz and in the frequency range 800 Hz to 2000 Hz. In the other frequency range, the sound insulation is approximately comparable. For single-values, the sound insulation is a few db higher for field measurements than laboratory measurements, for both Rw values and Rw + Ctr values (Rw = 30 db for field measurements and Rw = db for laboratory measurements and Rw + Ctr = 27 db for field measurements and Rw + Ctr = 24 db for laboratory measurements). Miljøstyrelsen / Åbne vinduer med god lydisolation 113

114 Noise Reduction, R / R' [db] FIGURE 50. Comparison of field measurement and laboratory measurements. All opened "4 cm" (Excellent opening area of 0.03 m 2 and internal opening area of 0.07 m 2 ). 60 ( M 4005 ) 50 ( M 4103 ) 40 ( M 4104 ) Frequency [Hz] Measurement no.. R w / R w R w+c tr / R w+c tr Description M Field Measurement. 1st floor. M Laboratory measurement. Without 20 mm absorbent at the top. M Laboratory measurement. With 20 mm absorbent at the top 10.4 Conclusion It seems that sound insulation is generally increased by field measurements rather than laboratory measurements - especially for the low frequency range (up to 200 Hz). An explanation for this could be the difference in sound incidence. In the laboratory, the sound field is diffused, which means that the sound comes from all directions (top, bottom, side, etc.) while the sound in the field is primarily spread slanted downwards (tire noise and engine noise). The difference between field measurements and laboratory measurements indicated as Rw + Ctr is 3-4 db, where field measurements show higher sound insulation than laboratory measurements. It cannot be denied that the difference could be greater in other window types, eg by the window types used in work packages 2 and 3, as the openings here are in the side and not in the bottom. By comparing the two field measurements on respectively. 1st and 2nd floor with "fully open" upside down, a difference of 2 db is detected by both Rw and Rw + Ctr, as the result on the second floor shows the lowest sound insulation. This could indicate that the greater the angle of the sound (here defined as the angle between the horizontal and the line between the road and the window), the lower the sound insulation. The Miljøstyrelsen / Åbne vinduer med god lydisolation 114

115 difference in window sound isolation depending on the angle of noise is, in another project, attempted simulated in the spacecraft simulation tool ODEON. The simulations partially confirm the results found at the field measurements, ie. That especially the high-frequency sound insulation falls when the noise's angle of inclination increases. The result is published in a paper presented at INTERNOISE in San Francisco, 2015 [33]. Miljøstyrelsen / Åbne vinduer med god lydisolation 115

116 11. Measurement on traditional open windows and selected main results from the project Illustration 11A. The window element used for the laboratory part of Chapter 10. The purpose of this chapter is to assemble various laboratory-proof sound insulation values for traditional open windows with different design and selected results from the project Traditional open window Sound insulation for different traditional windows in standard format (1230 mm x 1480 mm) has been measured in the laboratory. Photos of the windows are shown in Figure 11B, and the result of the measurements is shown in FIGURE 51. All windows were opened so the total opening area was 0.35 m2. The sound isolation is between 6-9 db for Rw and 5-8 db for R w+c tr. Miljøstyrelsen / Åbne vinduer med god lydisolation 116

117 M 5003 M 5004 M 5006 M 2019 M 3316 Illustration 11B. Photos of the traditional open windows shown in FIGURE 51. All photos except M 5006 is taken from the inside, while the M 5006 is taken from the outside. Miljøstyrelsen / Åbne vinduer med god lydisolation 117

118 Noise Reduction, R [db] FIGURE 51. "Common, open windows", see Illustration 11A. 60 ( M 5003 ) 50 ( M 5004 ) 40 ( M 5006 ) 30 ( M 2019 ) ( M 3316 ) Frequency [Hz] Description [db] [db] M M M M M Inward opening, side-hung Outward, top down Dannebrog window, outward opening, side-hung Two-winged, outwardly, under the hinge of mullion Two-winged, outwardly, under the hinge of the sides 11.2 Selected results from the project In FIGURE 52, selected results from the project (all with an opening area of 0.35 m 2 ) are compiled to provide an overall overview of found solutions and associated sound insulation. The window types used were: 1. Further development of the "windows window" 2. "Normal window" with interior solution 3. "Common Window" with external solution Window Type 1 has dimensions (width x height) 1250 mm x 2100 mm. Window types 2 and 3 have dimensions 1230 mm x 1480 mm (standard format), while the field measurement element (Air supply window) has dimensions of 910 mm x 2155 mm. The measurement results shown are for constructions or With and without absorbent. For work packages 2 and 3, the results shown for the prototype solutions are shown. For all solutions, the measured measurements are the best achievable while Miljøstyrelsen / Åbne vinduer med god lydisolation 118

119 Noise Reduction, R [db] maintaining 0.35 m 2 and the glass portions are not covered by an absorbent FIGURE 52. Selected results from the project. 60 ( M 1216 ) 50 ( M 1406 ) 40 ( M 2106 ) 30 ( M 2104 ) 20 ( M 3302 ) 10 ( M 3306 ) ( M 4109 ) 0 Frequency [Hz] Description [db] [db] M M M M M M M Window type 1 without frame absorber, see ch 7 Window type 1 with frame absorber, see ch 7 Window type 2 without frame absorber, see ch 8 Window type 2 with frame absorber, see ch 8 Window type 3 without frame absorber, see ch 9 Window type 3 with frame absorber, see ch 9 Field measurement element, see ch 10 It is seen from the measurements that there is a large spread between the achievable values, which is as expected based on the project's purpose. Here, solutions have been found that provide three different reductions, but are evenly distributed from a 12 db Rw + Ctr (window type 2) to 26 db (winch type 1) with a mid-way solution of 17 db ( Window type 3). Miljøstyrelsen / Åbne vinduer med god lydisolation 119

120 12. Conclusion Based on a previous project on "Air supply windows" ("Sound optimization of" Air supply windows ") [1] and an increasing need for sound insulation for open windows, a project entitled" Open windows with good sound insulation ". In general, three different window types are examined; I) Further development of the "windows window" II) "Standard window" with available solution and III) "Standard window" with external solution. An initial literature search has been performed for each of the three window types. For further development of the "Air supply window" there has been an increased focus on studies / methods that deal with lowfrequency sound insulation. Different methods based on resonators have been found. Common to these is that they deal with completely closed double constructions. In addition, other similar windows have been found, for example. Hafencity Fenster [22] and Plenum Window [14]. For the first reference, the opening area is considerably smaller than that in Denmark. The latter reference is a study in the sense of the noise approach taken on a scaled model. For the other two window types ("Common Window" with internal solution and "Common Wine Pigeon" with external solution), literature has been found describing different audio codec solutions, including Margretheholm [15] and Folehaven [16]. A considerable number of laboratory tests have been carried out with the various window types, both as mockup solutions and as more finished prototype solutions as well as some field measurements. This report explains the measurements and derived conclusions. Similar to previous studies, sound insulation for window types, among other things, is seen. To be dependent on dimensions, opening area and location of absorbent. The purpose of examining three different window types is to find alternatives to a common one Open window that extends broadly to sound insulation, but also extends broadly to dimensions, placement of absorbents and design additions, such as an ideal solution. An optimized version of the "Air supply window" has been developed, with special emphasis on sound insulation for the low frequency frequency range. Unlike earlier, perforated car has been developed, which is tuned to specifically handle the low-frequency part of the spectrum. It has been found that, with the perforated plates, improved sound insulation has been obtained at the lower frequencies and higher singlevalue values, where best achieved Rw of 30 db and Rw + Ctr of 26 db. A window has been developed that fits in a regular window hole with an interior solution. With reference in a single window, improvements are seen in several steps: first by adding an additional window (ie, a single double structure), then adding a slider window to the cavity and finally adding absorption to the frame structure. The clearest improvement is achieved by switching from single construction to double construction. Adding a removable element into the double structure also contributes to the overall increase in the reduction rate, especially if the absorption is also added to the double structure. The aim of the design was to increase the sound insulation approximately 5 db compared to a plain open window. For the solution, a Rw of 15 db and a Rw + Ctr of 12 db has been obtained, which is a total improvement for Rw of 8 db and for Rw + Ctr of 5 db in comparison to a common open window. A window has been developed that fits in a regular window hole with an external solution, and thus does not necessarily require changes to the window hole or window Miljøstyrelsen / Åbne vinduer med god lydisolation 120

121 The solution is based on an exterior design in the form of an attached sound loop connected to a window frame that opens into the sluice. With the optimum setup of absorbents in the audio loop, a sound insulation in the form of Rw of 21 db and Rw + Ctr of 17 db is an improvement for Rw of 14 db and for Rw + Ctr of 11 db compared to a common open window. Comparative field and laboratory measurements have been performed on a air supply window to investigate any differences between these. A higher sound insulation is observed for field measurements than laboratory measurements, especially for frequencies below 250 Hz. The difference in Rw + Ctr is 2-4 db. An explanation could be the difference in sound input, and therefore it cannot be denied that the difference could be greater in window types where the opening in the structure does not point to the noise source. For the overall project, it can be concluded that three window types have been studied that span widely in both sound insulation, dimensions and design / solution principle. For the three windows, a laboratory-proof sound insulation for Rw + Ctr has been obtained on respectively. 26, 12 and 17 db, where a generally open window has a sound insulation for Rw + Ctr of 5-8 db. Miljøstyrelsen / Åbne vinduer med god lydisolation 121

122 Appendix 1. References [1] Lydmæssig optimering af Air supply windowr, L. S. Søndergaard, H. S. Olesen, DELTA, [2] Designguide for bestemmelse af air supply windowrs lydisolation, L. S. Søndergaard, H. S. Olesen, DELTA, [3] Air supply windowr - Spørgeskemaundersøgelse og lydmålinger af Russervin- duer monteret i Kollektivhuset, Hans Knudsens Plads 1, 1. sal, Køben- havn, L. S. Søndergaard, H. S. Olesen, Miljøstyrelsen, Miljøprojekt nr. 1609, 2014, [4] Effectiveness of T-shaped acoustic resonators in low-frequency sound transmission control of a finite double-panel partition, Deyu Li, Xiao- Hong Zhang, Li Cheng, Ganghua Yu, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China, Journal of Sound and Vibration, May [5] Ph.D. Thesis Acoustic resonators for noise control in enclosures: Modelling, design and optimization, Ganghua Yu, Department of Mechanical Engineering, The Hong Kong Polytechnic University, November [6] Location optimization of a long T-shaped acoustic resonator array in noise control of enclosures, Ganghua Yi, Li Cheng, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China, Journal of Sound and Vibration, July [7] On the design of long T-shaped acoustic resonators, D. Li, J.S. Vipperman, Journal of Acoustical Society of America. [8] Noise control in enclosures: Modeling and experiments with T-shaped acoustic resonators, D. Li, L. Cheng, G.H. Yu, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China, J. S. Vipperman, Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pennsylvania, The Journal of the Acoustical Society of America, November [9] Design and resonant frequency prediction for long T-shaped acoustic resonators, D. Li, J.S. Vipperman, Department of Mechanical Engineering, University of Pittsburgh, Pennsylvania, The Journal of the Acoustical Society of America, [10] Control of sound transmission through double wall partitions using optimally tuned Helmholtz resonators, Stanislaw Pietrzko, Qibo Mao, Materials Science & Technology, EMPA, Dübendorf, Switzerland, ISMA [11] Dual Helmholtz resonator, M.B. Xu, A. Selamet, H. Kim, Department of Mechanical Engineering and The Center for Automotive Research, The Ohio State University, Columbus, United States, Applied Miljøstyrelsen / Åbne vinduer med god lydisolation 122

123 Acoustics, May [12] The acoustic performance of ventilated window with quarterwave resonators and membrane absorber, Z.H. Wang, C.K. Hui, C.F. Ng, Department of Civil and Evironmental Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, Applied Acoustics, September [13] Untersuchung der Schalldämmung von gekippten Einzel- Und Doppelfenstern. Sog. HafenCity Fenster sowie Fenster mit schallabsorbierenden Laibungs- und Sturzverkleidungen, F. Arnhold, B. Kögel, Zeitschrift für Akustik, SChallschutz und Schwingungstechnik, 2012 [14] Acoustical insertion loss of plenum window at different sound incidence angles, Y.G Tong, S.K. Tang, Department of Building Services Engineering, The Hong Kong Polytechnic University, Hong Kong, China, ICA 2010, August [15] Lydskodder til afskærmning mod støj fra virksomheder, L. R. Villefrance, Lloyds Register ODS, [16] Evaluering af støjprojekt i folehaven Københavns kommune, Teknik & Miljøforvaltningen, [17] Erfaringer med lydisolerende åbne vinduer i trafikstøjbelastede boligområder, B. Rasmussen, Statens Byggeforskningsinstitut, Aalborg Universitet, SBI 2015:08, 2015 [18] Rasmussen, B. (2015). Experiences with sound insulating open windows in traffic noise exposed housing. In C. Burroughs, & G. Maling (Eds.), Proceedings of Inter-Noise [Paper 833] Institute of Noise Control Engineering of the USA, Inc.. [19] Modeling and simulation of windows with noise mitigation and natural ventilation, X. Yu, F. CUI, S. Tan and K. Yao, Proceedings of Inter-Noise [Paper 1167] [20] Orientering fra Miljøstyrelsens Referencelaboratorium for Støjmålinger nr. 46/2012: Indendørs støjniveau med åbne vinduer. [21] Ny national kortlægning af vejstøj, Arbejdsrapport fra Miljøstyrelsen Nr. 2/2010 [22] Hamburger Leitfaden - Lärm in der Bauleitplanung 2010 [23] Acoustic Absorbers and Diffusers: Theory, Design and Application, Trevor J. Cox and Peter D Antonio, 2009 CRC press, ISBN [24] DS/EN ISO :2016 Akustik - Feltmåling af lydisolation i bygninger og af bygningselementer - Del 3: Facaders lydisolation [25] DS/EN ISO :2010 Akustik Laboratoriemåling af bygningselementers lydisolation Del 1: Produktspecifikke prøvningsprocedurer [26] DS/EN ISO :2010 Akustik Laboratoriemåling af bygningselementers lydisolation Del 2: Måling af luftlydisolation [27] DS/EN ISO :2010 Akustik Laboratoriemåling af bygningselementers lydisolation Del 4: Måleprocedurer og krav Miljøstyrelsen / Åbne vinduer med god lydisolation 123

124 [28] DS/EN ISO :2010 Akustik Laboratoriemåling af bygningselementers lydisolation Del 5: Krav til prøvningsfaciliteter og - udstyr [29] DS/EN ISO 717-1:1997 Akustik Vurdering af lydisolation i bygninger og af bygningsdele Del 1: Luftlydisolation [30] Støj fra veje, Vejledning fra Miljøstyrelsen Nr [31] Investigation of sound insulation for a Supply Air Window, L. S. Søndergaard and H. S. Olesen, Forum Acusticum 2011, DELTA [32] Investigation of sound insulation for a Supply Air Window field measurements and occupant response, L. S. Søndergaard and S. V. Legarth, Internoise 2014, DELTA [33] Investigating the impact of noise incidence angle on the sound insulation of a supply air window, M. B. Hansen, Internoise 2015, DELTA. Miljøstyrelsen / Åbne vinduer med god lydisolation 124

125 Appendix 2. About the laboratory measurements Measurement Space All laboratory measurements are performed in DELTA's measuring room at the Danish Technological Institute, Aarhus. The measuring facilities comprise three rooms in a row: a central room in the middle and a reception room on either side of the transmitter room. Illustration B1 shows a horizontal section in the measurement numbers, where room 1 is the transmitting room and room 2 and 3 receipt numbers. Figure B2 shows a vertical section in the measurement numbers. The gap between spaces 1 and 2 has dimensions of 2120 mm x 1250 mm, while the gap between spaces 1 and 3 has dimensions of 4210 mm x 2600 mm. Rooms 1, 2 and 3 have the volume according to Show m2, 64.8 m2 and 50.7 m2. The meter numbers meet all requirements of DS / EN ISO , Reference [28]. The large measuring gap between spaces 1 and 3 is adapted to the dimensions of the windows by building lightweight wall structures with high sound insulation in which the window opening is established. The approximate thickness of the two constructions are 220 mm and 320 mm respectively. Illustration B1. Horizontal section of the measuring spaces. Measured Values Measurement of window sound proofing in laboratory is performed according to "DS / EN ISO Series" Acoustics Laboratory Measurement of Building Elements Sound Insulation ", Reference [25] to [28]. The measurements are normally performed in 1/3 octave bands in the frequency range 100 Hz-5000 Hz, possibly in the extended frequency range 50 Hz-5000 Hz. The measurement result thus consists of a reduction numeral curve determined by the 18, alternatively 21, 1/3 octave values. Miljøstyrelsen / Åbne vinduer med god lydisolation 125

126 Illustration B2. Vertical section in the measurement numbers. In determining the reduction Figures for traditional windows, compensate for Window area. This means that measurement on the same window structure, but with different dimensions / areas (within certain limitations) will achieve almost the same measurement result. For example In comparison with products and for design purposes, to operate with a more manageable size, the 1/3 octave values are converted into a singlevalue, Rw, with two associated spectral adaptation stages C and Ctr according to "DS / EN ISO : 1997 ", reference [29]. For example, the main result of a sound insulation measurement in laboratory expressed as single-digit value will look like this: Rw (C; Ctr) = 38 (-2; -5) db The spectral adaptation path C and Ctr is added to the Rw value, thus adapting to the following noise types: Noise Source - Typical activities in a home (conversation, music, TV, etc.) - Playing kids - Medium and high-speed trains - Motorway traffic at more than 80 km / h - Jetfly, short distance - - Business noise in the medium and high frequency range Spectral adapter C - Road traffic in cities - Low speed train traffic - Propeller - Jetfly, big distance - Disco Music - - Business noise in the medium and low frequency range Ctr As mentioned above, the window area is included in the determination of the reduction Figures. In the case of closed windows (as well as the closed window closure window) these are considered as a traditional window, which is simply measured according to the DS / EN ISO method, reference [25] to [28]. However, opening the windows / openings, the design changes character from a traditional window to a design, which can rather be considered as a simple opening or channel through which the sound is transmitted. Sound transmission directly through the glass in an air supply window being of Miljøstyrelsen / Åbne vinduer med god lydisolation 126

127 less importance, the more windows are opened. Therefore, the above correction for window area when measured on traditional windows will not be optimal for open windows. This means that Rw (C; Ctr) for an open window applies only to the current window and not to correspondingly constructed windows of other dimensions. It could therefore be considered to use another target size for open windows, the element-normalized level differential, which, similar to the reduction rate, is measured according to the DS / EN ISO series. The target size is called Dn, e and the single-digit value Dn, e, w (C; Ctr). This method is intended for measurement on small building elements, often with an undefined area, such as Outdoor air valves and cable entries. By measuring according to this method, the soundproofing properties of open window constructions, but with different dimensions, could immediately be compared. As can be seen from the above, none of the two dimensions is obvious to Description of Open Window Sound Insulation. It is decided in this project to consider the designs as a traditional window, ie. That the sound insulation is specified as the reduction number and the single-digit value Rw (C; Ctr). Rw (C; Ctr) and Dn, e, w (C; Ctr) for all measurements included in this report are listed in Appendix 3. If Dn, e, w (C; Ctr) are determined, this can be done on the basis of the reduction values by a simple conversion. Measurement results are presented as curves, which indicate the reduction rate per. 1/3 octave, as well as the single number values Rw and Rw + Ctr. On each Figure, a number is identified that uniquely identifies the measurement (eg M 2019). This number refers to Appendix 3, where numerical values are given for the 1/3 octave reduction Figures. Miljøstyrelsen / Åbne vinduer med god lydisolation 127

128 Appendix 3. Measurement results in tabular form The terms M xxxx in the top row of each of the following tables are the number of the measurement used in connection with the report's Figures in Chapters Frequency M 1001 M 1004 M 1005 M 1007 M 1008 M 1108 M 1109 M 1110 M 1111 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 10,3 22,9 13,9 13,5 13, ,8 34,7 5,8 6,2 6,9 10,6 10,2 10,3 9, ,4 35,9 5,4 5,5 6,8 7,6 7,6 8,1 7, ,5 37,2 9,5 9,8 10,2 11,5 11,1 11,6 11, ,2 39,4 7,1 8,5 8,7 10,8 10,7 10,1 9, ,6 37,5 7,5 8,2 8,7 9,3 9,5 9,3 9, ,9 41,4 10,0 10,7 11,7 11,8 11,6 11,7 12, ,2 43,8 13,7 14,9 17,1 15,0 14,7 15,3 15, ,7 49,8 14,9 17,5 20,5 16,1 15,7 16,2 16, ,9 53,1 17,8 22,2 25,7 18,6 18,1 18,7 18, ,1 58,9 18,4 23,6 27,7 19,9 19,6 20,3 20, ,5 63,5 17,6 22,5 26,2 18,7 18,6 19,1 19, ,5 65,9 17,1 22,1 24,7 17,8 17,7 18,5 18, ,3 70,4 19,6 27,5 29,4 20,7 20,6 21,0 20, ,4 73,5 18,4 26,0 26,1 19,6 19,4 19,7 19, ,4 72,7 18,3 25,0 24,5 18,8 18,7 19,1 19, ,9 65,9 17,4 23,4 22,2 17,8 17,9 17,8 17, ,7 64,4 18,1 25,2 23,0 18,7 18,8 18,8 18, ,2 66,0 19,0 24,2 22,8 19,5 19,5 19,4 19, ,5 75,4 19,2 24,4 22,9 19,1 19,0 19,0 19, ,1 76,4 18,9 23,9 23,2 19,3 19,2 19,3 19,3 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 128

129 Frequency M 1208 M 1210 M 1213 M 1214 M 1216 M 1304 M 1306 M 1307 M 1310 [db] [db] [db] [db] [db] [db] [db] [db] [db] ,1 10,2 10,5 10,3 9,4 12,4 11,3 12,5 13,2 80 8,0 7,9 8,3 7,9 7,0 10,7 9,7 10,8 10, ,9 11,3 11,5 11,6 11,6 14,8 12,7 13,0 15, ,0 10,8 10,4 10,4 10,0 11,7 10,5 11,3 13, ,9 9,0 8,8 9,2 9,2 10,9 10,5 9,9 13, ,8 11,6 11,5 11,8 11,9 14,6 14,0 14,0 15, ,0 16,5 15,6 15,8 15,4 16,9 18,6 17,3 17, ,5 16,3 16,9 16,9 16,0 17,8 20,8 18,8 17, ,8 18,7 18,6 19,0 18,3 19,6 24,2 22,4 18, ,9 20,2 20,1 20,1 19,7 21,7 27,5 25,3 21, ,2 18,9 19,4 19,1 19,2 19,7 25,9 22,5 19, ,6 18,7 18,8 18,6 18,4 18,4 24,2 21,8 17, ,5 21,3 21,4 21,2 21,0 21,2 28,9 26,7 20, ,2 20,5 20,7 20,5 19,7 20,2 26,5 25,9 20, ,6 19,9 20,1 19,7 19,3 19,6 25,2 25,1 19, ,9 18,9 19,1 18,8 18,4 18,7 22,7 23,2 18, ,5 19,6 19,7 19,5 18,9 19,4 23,5 24,4 19, ,0 20,2 20,3 20,2 19,9 20,1 23,7 24,5 20, ,3 20,5 20,5 20,5 20,1 20,1 23,7 24,4 20, ,0 20,2 20,3 20,2 19,6 20,3 23,5 24,2 19,9 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 129

130 Frequency M 1317 M 1318 M 1319 M 1401 M 1402 M 1403 M 1404 M 1405 M 1406 [db] [db] [db] [db] [db] [db] [db] [db] [db] ,5 12,7 12,5 12,2-12, ,5 13,6 13,0 12,8 12,1 11,5 11,8 11,8 12, ,6 11,0 10,1 10,9 9,6 9,4 9,4 9,6 10, ,5 14,7 13,4 13,9 12,8 12,2 13,0 13,0 13, ,7 14,7 12,9 13,8 13,2 12,6 13,1 12,8 14, ,9 13,1 13,0 13,7 12,6 12,4 13,4 12,7 14, ,9 16,8 17,2 17,7 16,9 16,0 16,8 17,3 18, ,7 19,9 20,2 21,9 20,6 20,7 21,6 22,1 23, ,0 19,3 20,0 21,4 21,2 21,2 22,5 22,5 24, ,4 21,0 21,2 23,8 24,4 24,6 26,1 26,1 27, ,1 23,5 24,9 28,5 28,9 28,3 29,9 29,9 28, ,6 20,9 22,2 23,8 24,6 25,9 28,1 27,5 28, ,1 19,1 19,0 20,1 22,1 23,5 26,8 26,3 27, ,3 22,6 21,9 24,0 27,1 28,4 32,9 32,1 33, ,1 21,2 21,2 23,3 25,0 24,9 31,7 31,6 34, ,8 20,7 20,6 22,1 24,4 24,2 31,2 31,1 34, ,9 19,5 19,3 19,9 23,0 22,8 29,7 29,7 30, ,2 20,5 20,4 21,2 24,7 23,9 32,1 32,7 33, ,3 20,9 20,9 21,5 23,8 23,4 32,1 32,2 32, ,2 20,8 20,8 21,3 23,1 22,7 32,8 33,0 32, ,2 20,7 20,5 21,2 23,4 22,8 31,2 31,3 31,7 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 130

131 Frequency M 1501 M 1502 M 1504 M 1505 M 1506 M 1507 M 1601 M 1602 M 1604 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 18,4 15,7 15,5 14,2 14,4 15,2 19,8 12,8 12, ,1 11,7 10,2 13,2 13,1 14,4 33,0 11,0 12, ,4 5,9 6,4 10,9 10,4 10,0 35,0 6,9 9, ,0 6,7 8,7 11,5 10,0 9,8 37,2 11,4 14, ,9 9,8 11,3 12,9 11,5 11,4 42,6 11,9 15, ,3 8,8 12,7 14,3 13,0 13,5 41,7 9,1 14, ,8 10,1 14,2 15,0 13,8 14,0 42,3 11,7 18, ,9 11,5 17,2 17,4 16,4 16,6 47,2 13,9 21, ,4 13,2 17,6 16,8 16,4 15,9 51,5 15,2 22, ,3 13,9 20,4 16,2 17,9 17,5 54,7 18,9 25, ,9 16,6 24,1 18,0 21,9 23,0 59,9 19,6 29, ,0 15,9 18,3 16,2 18,0 19,2 63,8 18,9 24, ,2 16,1 19,0 15,3 18,7 20,5 65,6 18,2 21, ,7 17,2 19,8 18,0 21,1 22,1 67,6 20,3 25, ,3 16,2 19,0 17,6 21,5 21,9 70,4 19,7 25, ,5 15,3 17,2 16,8 19,2 19,3 68,1 19,6 23, ,6 14,7 16,7 16,3 19,6 19,4 64,9 18,8 20, ,8 15,1 16,9 16,4 19,4 19,6 65,1 20,0 21, ,6 15,8 17,6 17,0 20,6 20,5 67,9 20,8 22, ,1 15,8 17,5 17,3 20,2 19,8 74,5 20,3 22, ,5 15,8 17,0 16,9 19,1 18,9 73,0 20,1 22,1 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 131

132 Frequency M 1605 M 1606 M 1607 M 2001 M 2002 M 2003 M 2004 M 2007 M 2008 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 14,1 14,8 14,6 28,1 13,1 14,5 13,7 11,9 11, ,6 15,0 15,0 34,2 7,7 11,5 12,5 9,8 10, ,2 10,6 10,3 33,7 8,3 11,1 9,9 9,8 9, ,2 13,5 13,7 42,7 5,7 6,5 6,6 6,6 6, ,6 14,6 15,0 39,9 0,9 1,6 2,1 1,1 0, ,7 13,6 13,4 39,2 4,8 4,6 4,8 4,5 4, ,0 17,1 16,6 30,1 7,2 6,8 7,8 5,8 5, ,7 19,3 19,5 40,7 12,7 9,5 10,6 7,7 7, ,5 21,4 21,7 52,3 11,7 10,4 12,8 9,3 7, ,8 23,6 24,4 56,5 8,4 14,6 17,0 15,2 13, ,1 26,6 29,6 60,6 10,5 15,7 18,9 18,2 16, ,8 24,7 26,6 64,3 11,1 19,8 23,1 18,9 16, ,2 23,0 24,1 68,0 12,1 20,0 23,4 17,2 14, ,0 28,7 30,2 67,4 11,5 18,9 21,7 14,7 12, ,8 28,3 28,7 74,7 11,8 18,0 21,9 16,2 14, ,4 27,2 27,0 77,3 13,9 18,0 23,2 18,8 17, ,3 25,3 24,6 78,9 14,8 20,9 25,5 19,8 17, ,8 27,0 25,8 80,2 15,5 21,7 27,1 20,6 18, ,0 26,1 25,2 68,2 16,2 21,8 29,1 22,9 19, ,1 25,8 25,2 73,7 16,2 22,1 30,8 23,2 19, ,7 25,1 24,6 74,3 16,0 22,6 31,2 23,4 19,5 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 132

133 Frequency M 2009 M 2010 M 2011 M 2012 M 2013 M 2014 M 2015 M 2016 M 2017 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 12,2 12, ,1 12,6 23,2 23,6 11,6 63 9,8 9,7 9,9 9,6 8,6 8,7 34,8 34,5 4,6 80 9,2 9,0 9,5 9,3 8,2 8,5 33,5 34,1 3, ,2 6,3 6,3 6,3 5,3 5,3 37,5 38,2 8, ,2 1,1 1,8 0,8 0,5 1,4 36,3 35,6 11, ,7 4,5 4,7 4,6 4,6 5,1 34,2 34,2 5, ,0 6,6 6,8 6,6 6,8 6,9 24,8 24,5 8, ,6 8,5 9,3 9,1 10,4 10,9 38,3 37,3 12, ,2 9,2 10,3 9,0 10,2 10,7 51,0 48,4 10, ,7 15,2 16,5 14,6 14,2 15,5 55,6 52,5 12, ,0 18,4 18,3 17,1 15,1 16,7 60,1 59,0 11, ,3 17,4 18,2 17,0 14,4 15,6 63,3 57,9 10, ,1 14,6 17,2 15,4 12,7 13,3 67,0 65,8 10, ,6 13,8 16,3 14,9 12,9 13,4 67,9 63,6 9, ,8 15,7 17,0 15,8 13,9 14,8 74,0 68,8 9, ,2 17,7 18,2 16,4 15,3 16,7 74,0 70,7 10, ,8 18,4 18,1 16,2 16,0 17,2 75,6 71,5 11, ,0 19,3 18,4 16,8 16,6 18,1 75,3 61,5 11, ,9 21,2 19,3 17,0 17,7 19,6 66,2 58,6 12, ,1 21,5 19,2 17,0 17,8 20,0 72,0 67,7 12, ,3 21,7 19,0 17,1 17,8 19,8 71,9 72,6 13,0 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 133

134 Frequency M 2018 M 2019 M 2024 M 2025 M 2026 M 2027 M 2028 M 2029 M 2030 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 11,1 9,1 11,7 11,6 12,3 14,0 12,9 12,7 12,9 63 5,0 5,6 3,9 3,8 4,2 3,0 3,7 2,7 3,4 80 2,9 7,1 4,5 4,2 5,4 4,8 5,4 4,2 5, ,8 5,8 13,3 13,3 15,0 14,1 15,3 14,4 14, ,8 3,5 14,8 14,8 15,3 14,8 14,3 13,9 14, ,8 5,1 10,6 10,6 13,8 8,4 10,6 7,1 8, ,8 4,2 12,8 12,5 15,7 9,8 12,4 7,8 9, ,2 6,6 16,4 16,0 18,8 13,4 15,9 11,2 13, ,6 6,5 14,0 13,1 15,8 12,6 15,8 11,9 14, ,1 5,6 14,4 13,9 18,1 15,1 18,7 15,7 19, ,4 5,9 19,2 18,7 22,9 18,8 22,2 16,8 21, ,0 6,2 23,0 23,3 28,4 21,5 26,4 21,9 24, ,4 7,2 27,2 22,6 28,4 23,0 29,0 21,1 24, ,8 6,3 27,6 22,3 29,0 21,9 25,9 19,5 23, ,4 6,2 26,2 25,4 33,3 22,6 28,3 20,7 23, ,1 6,8 24,5 24,1 34,6 24,7 29,3 22,5 24, ,7 7,3 27,3 27,5 36,0 25,7 29,9 24,6 27, ,0 7,4 26,7 27,0 34,4 25,3 29,4 23,5 26, ,8 7,9 26,3 26,9 34,6 26,1 31,2 24,0 27, ,4 8,2 27,8 26,9 32,1 25,8 31,1 25,0 28, ,8 8,4 26,9 27,3 32,6 26,2 29,9 24,3 27,3 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 134

135 Frequency M 2031 M 2032 M 2033 M 2101 M 2102 M 2103 M 2104 M 2106 M 2107 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 10,1 9,9 8,9 16, , ,6 1,8 2,2 30,3 30,7 29,5 14,5 14,9 14,0 80 4,3 3,8 3,8 30,2 29,6 30,3 7,7 7,9 7, ,0 14,6 14,0 36,2 35,8 36,5 6,9 7,3 7, ,5 11,5 10,1 33,7 33,9 32,7 3,8 3,4 6, ,5 6,2 5,7 32,6 33,1 32,2 4,2 4,1 6, ,8 8,7 9,4 26,9 28,4 26,9 7,4 7,7 9, ,5 9,5 13,0 40,9 40,2 41,5 6,5 7,0 8, ,6 12,1 9,2 49,5 49,0 49,9 7,1 6,7 8, ,0 15,8 9,0 48,9 50,8 49,3 10,9 10,1 12, ,7 16,4 10,8 56,3 56,1 57,0 14,9 13,9 14, ,7 17,6 13,0 59,6 58,9 60,6 15,9 14,6 16, ,9 18,6 15,8 61,9 61,7 62,8 12,9 11,7 13, ,5 18,6 14,9 62,7 62,6 63,4 12,1 10,9 12, ,8 18,3 14,6 65,8 65,2 66,0 14,1 11,8 13, ,8 19,6 16,2 66,4 65,4 66,6 16,5 13,3 14, ,3 20,3 16,7 65,4 65,3 66,2 17,0 13,3 14, ,6 20,2 16,7 64,0 64,4 68,4 18,1 13,6 15, ,2 21,8 17,0 62,8 61,9 71,2 19,4 14,9 16, ,4 22,3 17,7 72,8 71,5 75,1 19,5 15,2 16, ,0 21,8 17,3 74,3 73,7 74,2 19,2 15,4 16,8 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 135

136 Frequency M 2108 M 2109 M 3001 M 3002 M 3005 M 3011 M 3012 M 3013 M 3014 [db] [db] [db] [db] [db] [db] [db] [db] [db] ,6 15,9 14,0 16,4-16,2 16, ,1 17,1 9,6 9,6 7,8 7,8 6,6 5,8 6,3 80 8,2 11,1 5,6 4,7 4,6 4,0 3,7 3,1 3, ,7 10,0 2,7 1,8 3,2 5,6 5,8 7,3 6, ,0 4,9 6,0 2,7 7,5 5,3 5,7 8,0 7, ,2 5,3 5,6 4,0 7,5 5,6 6,5 8,2 8, ,2 8,8 9,1 8,9 10,8 9,0 9,9 11,6 11, ,2 9,0 9,6 9,8 7,7 8,3 9,9 11,6 11, ,8 9,0 7,5 7,6 6,9 8,6 9,8 11,9 11, ,5 10,9 7,4 7,8 8,9 8,1 9,3 12,2 12, ,9 12,2 9,1 9,2 9,6 9,4 11,2 14,2 14, ,0 15,0 9,2 9,8 9,4 10,1 11,6 15,3 15, ,5 15,2 10,0 10,4 9,4 10,9 12,9 17,0 16, ,4 14,9 11,3 11,7 10,9 12,0 14,0 19,2 18, ,6 15,7 11,1 11,5 10,2 12,5 14,6 22,4 21, ,4 17,1 11,4 11,7 10,9 12,6 14,2 24,2 21, ,4 16,8 11,8 11,8 11,4 12,7 14,2 26,3 20, ,0 16,7 11,9 11,9 11,1 12,9 14,2 28,2 21, ,6 17,0 12,4 12,6 11,7 13,4 14,4 31,3 22, ,6 17,8 12,7 12,9 12,2 13,9 15,1 33,3 23, ,3 18,0 12,7 13,3 12,4 14,2 15,5 31,3 23,2 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 136

137 Frequency M 3015 M 3016 M 3017 M 3018 M 3019 M 3020 M 3102 M 3103 M 3105 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50-16,4 16,1 16, , ,3 5,8 9,8 8,4 8,3 9,1 4,4 6,0 8,5 80 3,9 4,2 5,3 4,9 5,0 5,8 1,6 3,0 3, ,4 9,5 3,7 4,9 6,8 3,5 8,9 9,4 8, ,0 10,4 4,3 4,8 6,8 3,4 11,0 12,6 5, ,6 10,1 4,7 5,6 7,9 4,5 12,7 13,5 11, ,1 13,1 10,3 11,3 12,6 9,4 13,5 14,0 17, ,1 13,9 10,2 11,2 12,6 9,4 9,4 10,5 14, ,0 13,9 8,8 9,8 11,3 7,7 10,0 11,6 11, ,3 14,9 9,2 10,6 12,0 8,0 12,1 14,2 11, ,1 16,9 10,8 12,7 14,3 9,7 13,8 16,4 16, ,2 18,2 11,3 13,0 14,8 9,9 14,5 17,5 19, ,3 19,4 12,0 14,5 16,2 10,4 14,3 17,4 18, ,7 22,3 13,6 16,4 18,4 11,9 11,9 14,7 16, ,8 25,7 13,6 18,8 21,1 11,9 12,8 16,2 17, ,8 28,3 13,6 19,9 22,9 12,2 13,2 16,5 17, ,0 31,0 13,6 21,4 24,6 12,3 13,4 16,4 17, ,5 32,7 13,4 22,9 25,8 12,4 13,6 16,3 17, ,3 35,2 13,8 24,6 26,5 13,0 14,2 16,4 17, ,2 35,2 14,5 25,1 26,1 13,2 14,4 16,0 16, ,0 33,1 14,4 24,8 25,4 13,2 14,3 16,2 16,7 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 137

138 Frequency M 3106 M 3107 M 3108 M 3109 M 3110 M 3111 M 3112 M 3113 M 3114 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50-15,0 15, ,8 8,8 9,0 9,4 15,8 9,7 9,1 11,0 10,6 80 3,6 4,3 4,6 4,5 12,6 4,6 4,4 5,4 5, ,0 9,3 9,2 9,1 15,7 10,5 10,9 10,4 10, ,2 6,4 6,9 6,4 8,2 11,6 12,6 13,9 14, ,3 11,8 12,3 12,1 10,0 14,3 14,2 14,8 15, ,1 18,4 18,4 18,6 14,1 16,6 14,9 14,7 15, ,6 16,6 16,5 16,9 13,8 14,5 13,7 14,1 14, ,6 13,0 13,5 14,0 12,3 13,7 15,7 16,2 17, ,8 13,5 14,1 14,5 12,0 15,1 17,7 18,2 19, ,1 18,2 19,0 19,3 15,2 17,4 20,1 21,0 22, ,9 22,6 23,2 23,5 17,6 20,5 23,4 24,2 25, ,8 23,4 23,8 24,2 18,9 22,7 24,4 25,6 26, ,6 21,4 21,9 22,4 19,1 21,9 22,5 24,8 25, ,3 23,1 23,7 24,4 20,7 24,0 24,2 27,0 28, ,7 24,4 25,1 25,9 22,0 25,1 25,6 28,7 29, ,8 24,6 26,4 26,6 22,5 26,0 26,6 29,7 32, ,9 25,3 27,0 27,4 22,8 26,9 27,6 31,2 34, ,4 25,2 28,0 28,6 23,5 28,3 29,1 32,0 35, ,9 24,3 28,1 28,4 23,7 28,4 28,9 29,5 35, ,6 24,0 27,7 28,5 24,0 28,0 28,8 27,9 33,9 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 138

139 Frequency M 3115 M 3204 M 3205 M 3206 M 3207 M 3208 M 3209 M 3210 M 3211 [db] [db] [db] [db] [db] [db] [db] [db] [db] ,5 17, ,5 63 7,9 11,3 12,3 11,6 12,1 12,2 12,3 12,2 8,6 80 3,4 9,1 8,9 9,1 8,8 9,8 10,5 9,7 7, ,7 7,9 7,8 8,3 8,1 8,1 8,3 8,9 8, ,0 5,4 5,2 6,0 5,8 6,2 6,6 6,1 7, ,5 5,1 5,7 6,8 5,7 6,0 6,9 6,7 9, ,3 5,5 5,6 7,5 6,3 7,0 7,9 8,4 10, ,4 6,2 6,7 9,4 7,7 8,4 9,8 10,1 11, ,4 6,3 6,5 9,3 8,0 8,5 10,0 10,3 12, ,7 6,8 7,1 10,6 8,6 10,1 11,9 12,0 14, ,0 7,9 8,3 12,3 10,4 11,6 13,7 14,1 16, ,2 9,0 10,0 15,0 13,0 13,9 16,3 16,6 20, ,4 9,8 10,8 17,6 15,1 16,9 18,8 19,7 23, ,7 9,9 11,0 19,4 16,5 18,2 20,8 21,3 25, ,1 10,9 12,5 21,2 18,3 20,1 22,5 23,0 28, ,7 11,0 12,3 22,6 19,3 20,8 23,8 24,2 30, ,5 11,2 12,6 24,0 20,9 22,3 25,4 25,9 33, ,7 11,0 12,2 24,2 21,7 24,1 26,5 26,9 35, ,5 11,1 12,2 22,7 21,4 25,7 27,1 27,5 31, ,0 11,4 12,4 21,4 21,1 26,8 27,6 28,1 29, ,6 11,1 12,1 20,3 20,3 26,2 27,3 28,0 27,0 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 139

140 Frequency M 3212 M 3213 M 3214 M 3215 M 3301 M 3302 M 3303 M 3304 M 3305 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50 18, , ,2 63 7,8 8,8 9,0 9,5 27,2 7,8 8,1 8,0 7,7 80 6,2 6,4 6,7 6,2 21,6 6,0 6,8 6,3 6, ,1 7,3 6,5 5,9 21,9 5,6 5,5 9,3 9, ,9 5,4 5,1 4,0 20,4 3,4 3,6 6,0 6, ,8 7,5 6,3 6,2 19,5 5,9 6,0 8,7 9, ,9 8,3 7,2 6,7 20,5 5,7 5,7 8,7 9, ,7 9,3 7,4 6,6 27,1 6,1 6,1 10,3 10, ,6 9,4 7,1 6,1 31,0 5,7 6,0 10,7 12, ,1 11,3 8,3 7,1 31,8 6,5 6,9 12,6 13, ,8 13,5 9,5 8,1 36,9 7,6 8,1 14,4 15, ,2 16,3 11,1 9,3 39,0 8,6 9,0 17,5 18, ,4 20,0 12,5 10,2 41,7 8,8 9,5 20,8 21, ,0 21,4 12,5 10,2 44,6 9,3 10,1 23,1 24, ,5 23,7 13,8 11,2 47,9 10,3 11,1 25,9 26, ,5 25,3 13,3 11,1 49,4 10,2 11,1 27,1 27, ,9 28,4 13,3 11,3 50,3 9,7 10,8 27,9 27, ,7 30,8 13,2 11,2 48,0 10,0 10,9 28,3 28, ,7 29,8 13,3 11,5 46,7 10,9 11,5 26,1 25, ,8 27,0 13,4 11,3 51,0 11,2 11,9 24,5 24, ,4 25,3 13,4 11,8 54,5 11,6 12,1 24,0 24,5 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 140

141 Frequency M 3306 M 3309 M 3311 M 3312 M 3316 M 4001 M 4002 M 4003 M 4004 [db] [db] [db] [db] [db] [db] [db] [db] [db] 50-18,3-19,1 14,5 17,6 28,9 15,3 28,3 63 7,4 7,4 7,0 6,9 9,6 8,7 23,4 11,4 32,9 80 6,2 6,5 6,8 6,1 6,6 11,0 28,8 8,1 30, ,5 8,0 6,7 8,3 5,7 10,2 29,6 13,8 27, ,8 4,9 3,8 5,2 5,8 9,4 33,0 13,3 30, ,2 7,3 6,4 8,5 5,5 13,9 30,9 14,9 31, ,1 6,9 5,7 8,4 5,6 16,6 34,3 19,3 33, ,3 9,0 6,1 10,2 5,6 16,6 33,2 17,9 33, ,9 9,1 6,1 11,4 5,3 19,9 31,9 20,7 31, ,8 10,6 6,7 12,5 5,2 23,3 32,9 23,7 30, ,0 12,5 8,0 14,6 5,9 21,3 35,7 24,4 34, ,1 15,4 9,2 17,5 6,8 20,3 40,2 21,1 38, ,2 18,2 10,0 20,7 6,5 24,7 44,0 26,0 43, ,5 20,5 10,6 23,3 6,2 24,4 47,2 25,3 44, ,1 22,7 11,5 25,4 6,8 23,9 47,7 25,7 46, ,3 24,3 11,5 27,1 7,3 22,2 46,8 24,1 44, ,6 25,7 11,2 28,0 7,5 23,8 43,5 25,8 45, ,9 27,7 11,3 28,3 8,1 24,8 41,2 26,7 42, ,5 26,9 11,9 26,0 8,4 24,3 37,9 26,5 38, ,7 25,2 12,5 24,7 8,5 22,2 32,9 25,2 33, ,5 24,7 12,6 24,3 8,8 20,6 29,3 22,5 28,9 R w / R w C C tr D n,e,w / D n,e,w C C tr Miljøstyrelsen / Åbne vinduer med god lydisolation 141