OLIVE VILLAS, SANDOWN LANE, LIVERPOOL, L15 4HU

Transcription

1 MEASUREMENT OF THE SOUND INSULATION OF SEPARATING FLOORS on behalf of URBAN BUBBLE LTD for the development at OLIVE VILLAS, SANDOWN LANE, LIVERPOOL, L15 4HU REPORT DATE: 14 OCTOBER 2015 REPORT NUMBER: AUTHOR: Colin Foster MIOA ANC Registration Number: 152 Miller Goodall Environmental Services Ltd 214 Turton Road Bradshaw Bolton BL2 3EE Company registration number

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3 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Prepared By Colin Foster Reviewed By Joanne Miller Signed Signed Date 14 October 2015 Date 14 October i

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5 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Contents 1 Introduction 2 2 Property Details 2 3 Measurement Procedure Airborne Measurements Impact Measurements Test Details Test Equipment Test Results 5 5 Subjective Assessment 6 6 Discussion 6 7 Conclusions 7 Appendix 11 Impact Test No. Test_I_ Impact Test No. Test_I_ Impact Test No. Test_I_ Impact Test No. Test_I_ Impact Test No. Test_I_ Airborne Test No. Test_A_ Airborne Test No. Test_A_ Airborne Test No. Test_A_ Airborne Test No. Test_A_ Airborne Test No. Test_A_ i

6 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd 1 Introduction This report details the results of measurements of the airborne and impact sound insulation of separating floors within a residential development. Details of subjective listening tests are also provided together with information obtained from the residents who were interviewed during the survey with respect to the noise disturbances they currently experience. The results of the measurements were also compared with the performance standards provided in Section 0 of Approved Document E to the Building Regulations 2000, 2003 edition, amended 2004 (Ref 1). This survey was requested by the client as a result of noise complaints received from some occupants of the development. The client was Urban Bubble Ltd of 79 Tibb Street, Manchester, M4 1CS. 2 Property Details The measurements were undertaken within Olive Villas, Sandown Lane, Liverpool, L15 4HU. The development underwent major conversion and refurbishment works within the last 10 years in which 20 flats were formed within two separate buildings. Number 38 is a 4 storey property which currently contains a total of 8 flats, 2 on each floor. We understand that the original building was re-built in the 1950 s, after sustaining bomb damage during the war. Number 40 is a 4 storey property which currently contains a total of 12 flats. The construction of the separating walls and floors in of either of the buildings is not known and was not investigated in any detail during the survey. It is considered likely that the separating floors are constructed using the original timber joists and tongue and groove floor, together with an upgrade of either a floating floor or an independent ceiling. We understand that complaints have been received from residents of both buildings and that these complaints relate to creaking noises being audible through the floor when occupants of the flat above are moving around. We further understand that formal pre-completion sound insulation tests were not undertaken in either building following the refurbishment works. 2 of October 2015

7 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU 3 Measurement Procedure 3.1 Airborne Measurements The airborne tests detailed in this report were carried out in general accordance with the requirements of BS EN ISO 140-4:1998 (Ref 2). A single figure rating of the airborne sound insulation performance, known as the Weighted Standardized Level Difference, D nt,w + C tr, was derived from these measurements in accordance with the British Standard BS EN ISO 717-1:1997 (Ref 3). 3.2 Impact Measurements The impact sound insulation of the separating floor was measured in general accordance with BS EN ISO 140-7:1998 (Ref 4). The performance of the floor was rated in terms of the Weighted Standardized Impact Sound Pressure Level L nt,w, in accordance with BS EN ISO 717-2:1997 (Ref 5). 3.3 Test Details Testing was carried out between the hours of 9:30 am and 4 pm on 9 th October The person in charge of the testing was Colin Foster of Miller Goodall Environmental Services Ltd. The following tests were performed on the separating floors, as shown in Table 1 Table 1 Test Details Type of Test Test Number Source Room Vol m 3 Description of Test Receiver Room Vol m 3 Common Area m 2 Impact Test_I_1 No.40, Flat 12, 3F Lounge 74 No.40, Flat 9, 2F Lounge Impact Test_I_2 No.40, Flat 12, 3F Bedroom 17 No.40, Flat 9, 2F Bedroom Impact Test_I_3 No.40, Flat 9, 2F Lounge 72 No.40, Flat 6, 1F Lounge Impact Test_I_4 No.38, Flat 6, 2F Lounge 32 No.38, Flat 4, 1F Bedroom Impact Test_I_5 No.38, Flat 4, 1F Lounge 96 No.38, Flat 6, 2F Bedroom Airborne Test_A_1 No.40, Flat 12, 3F Lounge 74 No.40, Flat 9, 2F Lounge Airborne Test_A_2 No.40, Flat 12, 3F Bedroom 17 No.40, Flat 9, 2F Bedroom Airborne Test_A_3 No.40, Flat 9, 2F Lounge 72 No.40, Flat 6, 1F Lounge Airborne Test_A_4 No.38, Flat 6, 2F Lounge 32 No.38, Flat 4, 1F Bedroom Airborne Test_A_5 No.38, Flat 4, 1F Lounge 96 No.38, Flat 6, 2F Bedroom of 22

8 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd All windows and doors to all the living accommodation were closed for the duration of the tests and all the rooms were directly adjacent to one another. The most significant noise source in rooms to the front of the building was occasional road traffic from Sandown Road. However, the background noise in the rooms was generally low for the duration of the tests and did not adversely affect the measurements. All of the test rooms were contained within occupied flats which were fully furnished. Carpet had been laid in each of the rooms under test and it was not possible to remove this for the impact tests. Therefore, the tapping machine was placed onto a piece of chipboard of approximately 10 mm thickness and measuring approximately 1 m Test Equipment The test equipment used is shown in Table 2, below. Table 2 Equipment Used Equipment Description Type Number Manufacturer Serial No. Calibration Date Calibration Certification Number Class 1 Integrating Real Time 1/3 Octave Sound Analyser Type 2260 Brϋel & Kjær /08/15 U19540 Microphone Type 4189 Brϋel & Kjær /08/15 U19538 Calibrator Type 4231 Brϋel & Kjær /08/15 U19539 Graphic Equaliser Type 131v dbx N/A N/A Wireless Transmitter/ Receiver Omni Directional Dodecahedron Sound Source Type PT-60/ SR-60 AKG N/a N/A N/A Type 4296 Brϋel & Kjær N/A N/A Power Amplifier Type 2716 Brϋel & Kjær N/A N/A Tapping Machine Type 3207 Brϋel & Kjær /05/ /1 4 of October 2015

9 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU 4 Test Results There were a total of ten tests and the results are given in Table 4 below. The results have been compared with the performance standards provided in Section 0 of Approved Document E to the Building Regulations 2000, 2003 edition, amended 2004 (Ref 1). Table 1 Summary of Results Test Type Impact Impact Impact Impact Impact Test No. Test_I_1 Test_I_2 Test_I_3 Test_I_4 Test_I_5 Airborne Test_A_1 Airborne Test_A_2 Airborne Test_A_3 Airborne Test_A_4 Airborne Test_A_5 Source Room Receiver Room Description m 3 Description m 3 No.40, Flat 12, 3F Lounge No.40, Flat 12, 3F Bedroom No.40, Flat 9, 2F Lounge No.38, Flat 6, 2F Lounge No.38, Flat 4, 1F Lounge No.40, Flat 12, 3F Lounge No.40, Flat 12, 3F Bedroom No.40, Flat 9, 2F Lounge No.38, Flat 6, 2F Lounge No.38, Flat 4, 1F Lounge No.40, Flat 9, 2F Lounge No.40, Flat 9, 2F Bedroom No.40, Flat 6, 1F Lounge No.38, Flat 4, 1F Bedroom No.38, Flat 6, 2F Bedroom No.40, Flat 9, 2F Lounge No.40, Flat 9, 2F Bedroom No.40, Flat 6, 1F Lounge No.38, Flat 4, 1F Bedroom No.38, Flat 6, 2F Bedroom Measured D ntw + C tr in db Measured L' ntw in db Required Sound Insulation in db (Ref Error! Bookmark not defined.). Pass / Fail Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Partitions with higher values of D nt,w correspond to better airborne sound performance. Conversely, in the case of impact sound, lower values of (L' nt,w) represent better performance. Full results of the airborne tests (Weighted Standardized Level Difference (D nt,w)) and the impact tests (Weighted Standardized Impact Sound Pressure Level (L' nt,w)) are shown in the Appendix. 5 of 22

10 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd 5 Subjective Assessment During the site visit, several residents were questioned with respect to the noise disturbances they currently experience. It was stated that the perceived level of noise disturbance was high, particularly in the evenings and early mornings (when background noise levels are generally lower). The main type of disturbance which was mentioned related to creaking sounds whenever people move around in the flats directly above. It was felt by those interviewed that the creaking sounds appeared to be generated as a result of people moving around and caused the ceiling of the affected flats to creak and vibrate. It was stated that the affected occupants were able to determine the approximate location and travel directions as people move around in flats directly above, and that some footstep noise was audible. It was stated that there was little or no disturbance resulting from the transfer of general airborne sounds between flats, such as conversations, TV, music and the like. During the course of the survey, the author of this report undertook subjective listening tests whilst a second engineer from Miller Goodall walked normally around the flat above. The author verified that the creaking floor/ceiling sounds were audible and at sufficient level so as to potentially cause a disturbance to some people. The occupant of Flat 6 of No.38 mentioned there was excessive noise transfer between his bedroom and the lounge of the Flat 4, located directly below, and that the noise transfer was particularly bad in one corner of his room. Subjective listening tests undertaken by the author during the survey confirmed that this was the case and also identified one corner of the room as being particularly noticeable as performing worse. 6 Discussion From the results given, it can be seen that all of the tested floors passed the sound insulation criteria for Building Regulations approval, for airborne and impact sound. Furthermore, the floors passed the criteria by a significant margin, particularly those tested within no.38. However, it is to be appreciated that compliance with the Building Regulations standards does not result in the total attenuation of sound transfer between dwellings. Subjective listening tests have verified the claims of some residents relating to the audibility of creaking noises and other low frequency sound from certain flats to those below. It is our understanding that the residents are considerate adults and are unlikely to engage in activities which cause excessive impact sound such as aerobics, or by having small children running around the flats. It is therefore considered unlikely that the noise complaints are as a result of any of the residents engaging in particularly unusual or anti-social activities. 6 of October 2015

11 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU This survey was limited to a non-invasive test of the existing floors. Detailed inspections of the floor constructions are beyond the scope of this work and, as such, it was not possible to determine the causes of the creaking noise or to recommend appropriate mitigation measures. However, based on experience gained on similar projects, the noise is likely to be caused by relatively large deflections in the timber joists as people walk around the flats. These deflections result in the creaking of timber joists and, in some rooms, caused the ceiling light fittings to visibly shake. This problem is very low frequency in nature and below the frequency range which the Building Regulations cover. Therefore, the situation arises in which the floors satisfy the Building Regulations requirements and yet there are still noise issues which are resulting in genuine noise complaints from residents. If the residents wish to undertake any additional building work to mitigate the existing noise complaints then it is important that an Acoustic Consultant is involved to ensure that the work is effective and worthwhile. The creaking sounds are unlikely to be sufficiently reduced by the application of any further treatment to the floor finish (i.e. thicker carpets, underlay or other resilient elements). We recommend that any further inspection surveys should initially concentrate on identifying whether all of the resilient elements (e.g. the floating floor and the independent or resilient ceiling) have been installed properly and are not being bridged or by-passed in some way. It is possible that the creaking sounds could be reduced by adding structural elements to stiffen up the floors and reduce the deflection under dynamic loads. 7 Conclusions Miller Goodall was commissioned to undertake objective and subjective measurements of the airborne and impact sound insulation of separating floors within numbers 38 and 40 Sandown Road in Liverpool. The tests were instructed following several noise complaints relating to excessive sound transmission through the floors, which had been received since refurbishment works were completed at the properties. The results of the measurements confirmed that the all of the tested floors achieved the performance standards provided in Section 0 of Approved Document E to the Building Regulations 2000, 2003 edition, amended 2004 (Ref 6). The tests indicated that the tested floor constructions in no.38 were better than those in no.40. Subjective listening tests confirmed that creaking sounds were clearly audible in the flats whenever a person was moving around in the flat directly above. Furthermore, the level of the creaking sound was considered to be sufficiently high to have the potential to cause a noise disturbance to noisesensitive people, particularly if the movements occurred late at night or very early in the morning. 7 of 22

12 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd Detailed investigative works on the tested floors were beyond the scope of this work and therefore it was not possible to accurately determine the causes of the creaking noise or to suggest possible mitigation measures. If further investigative survey work is to be undertaken then we would recommend these should initially concentrate on identifying whether all of the resilient elements have been installed properly and are not being bridged or by-passed in some way. The creaking noises may be reduced by adding structural members in order to stiffen the timber floor joists and reduce the amount of floor deflection under dynamic loads. It is considered unlikely that increasing the thickness or quality of the soft floor coverings upon the floors will result in any significant improvement. We would recommend that an Acoustic Consultant be appointed to advise on the extent of any further building works before they are carried out. 8 of October 2015

13 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU References 1 Approved Document E to the Building Regulations 2000, 2003 edition, amended 2004: Resistance to the passage of sound 2 BS EN ISO 140-4:1998 Acoustics Measurement of sound insulation in buildings and of building elements Part 4: Field measurements of airborne sound insulation between rooms 3 BS EN ISO 717-1:1997 Acoustics Rating of sound insulation in buildings and of building elements. Part 1. Airborne sound insulation. 4 BS EN ISO 140-7:1998 Acoustics Measurement of sound insulation in buildings and of building elements Part 7: Field measurements of impact sound insulation of floors 5 BS EN ISO 717-2:1997 Acoustics Rating of sound insulation in buildings and of building elements. Part 2 Impact Sound Insulation 6 Approved Document E to the Building Regulations 2000, 2003 edition, amended 2004: Resistance to the passage of sound 9 of 22

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15 Appendix

16 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd Impact Test No. Test_I_1 Standardized Impact Sound Pressure Level according to ISO Field measurements of impact sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 L'nT Curve Ref Curve Shifted Ref Curve Description of test: No.40, Flat 12, 3F Lounge to No.40, Flat 9, 2F Lounge Partition construction: Unknown Source room volume: 74 m 3 Receiver room volume: 72 m 3 Common area: 23 m 2 Freq (Hz) L' nt (db) B 60.3 B 60.5 b 57.4 b 55.5 B 53.4 B 48.3 B 45.5 B 40.3 B 36.9 B 30.9 B 29.0 B 27.2 b B 24.3 B B 20.5 B B 18.5 B B b or B indicates correction for background noise B also indicates limit of measurement Rating according to ISO L' ntw = 51 db Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method. Report test no.: Test_I_1 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 12 of October 2015

17 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Impact Test No. Test_I_2 Standardized Impact Sound Pressure Level according to ISO Field measurements of impact sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 L'nT Curve Ref Curve Shifted Ref Curve Description of test: No.40, Flat 12, 3F Bedroom to No.40, Flat 9, 2F Bedroom Partition construction: Unknown Source room volume: 17 m 3 Receiver room volume: 33 m 3 Common area: 10 m 2 Freq (Hz) L' nt (db) B 60.0 B 60.4 b 58.9 b 59.0 B 60.9 B 55.7 B 51.7 B 47.8 B 44.8 B 37.4 B 27.6 B 23.5 b B 23.3 b B 18.9 B B 14.7 B B b or B indicates correction for background noise B also indicates limit of measurement Rating according to ISO L' ntw = 54 db Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_I_2 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 13 of 22

18 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd Impact Test No. Test_I_3 Standardized Impact Sound Pressure Level according to ISO Field measurements of impact sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 L'nT Curve Ref Curve Shifted Ref Curve Description of test: No.40, Flat 9, Lounge to No.40, Flat 6, 1F Lounge 2F Partition construction: Unknown Source room volume: 72 m 3 Receiver room volume: 80 m 3 Common area: 23 m 2 Freq (Hz) L' nt (db) 65.7 B 61.4 B 59.0 b 54.7 b 51.4 B 51.4 B 47.5 B 44.8 B 38.8 B 34.4 B 28.0 B B 27.2 b B 28.2 B 28.1 B 26.9 b B 33.1 B b or B indicates correction for background noise B also indicates limit of measurement Rating according to ISO L' ntw = 51 db Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_I_3 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 14 of October 2015

19 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Impact Test No. Test_I_4 Standardized Impact Sound Pressure Level according to ISO Field measurements of impact sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 L'nT Curve Ref Curve Shifted Ref Curve Description of test: No.38, Flat 6, Lounge to No.38, Flat 4, 1F Bedroom 2F Partition construction: Unknown Source room volume: 32 m 3 Receiver room volume: 33 m 3 Common area: 13 m 2 Freq (Hz) L' nt (db) 60.8 B 56.9 B 59.4 b 55.3 b 49.2 B 51.5 B 46.8 B 40.1 B 33.1 B 27.7 B 24.2 B 20.7 B 16.6 b B 16.0 b B 12.7 B B 10.9 B B b or B indicates correction for background noise B also indicates limit of measurement Rating according to ISO L' ntw = 49 db Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_I_4 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 15 of 22

20 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd Impact Test No. Test_I_5 Standardized Impact Sound Pressure Level according to ISO Field measurements of impact sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 L'nT Curve Ref Curve Shifted Ref Curve Description of test: No.38, Flat 4, Lounge to No.38, Flat 6, 2F Bedroom 1F Partition construction: Unknown Source room volume: 96 m 3 Receiver room volume: 52 m 3 Common area: 18 m 2 Freq (Hz) L' nt (db) 55.2 B 53.8 B 50.8 b 48.1 b 48.5 B 48.3 B 42.6 B 38.0 B 33.3 B 28.6 b B 24.2 b B 23.5 B B 22.2 B B 16.9 B B 17.8 B B 15.8 B B b or B indicates correction for background noise B also indicates limit of measurement Rating according to ISO L' ntw = 44 db Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_I_5 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 16 of October 2015

21 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Airborne Test No. Test_A_1 Standardized Level Difference according to ISO Field measurements of airborne sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 DnT Curve Ref Curve Shifted Ref Curve Description of test: No.40, Flat 12, 3F Lounge to No.40, Flat 9, 2F Lounge Partition: Floor Partition construction: Unknown Source room volume: 74 m 3 Receiver room volume: 72 m 3 Common area: 23 m 2 Freq (Hz) D nt (db) B 36.5 B 37.6 b 40.5 b 41.7 B 44.2 b B 48.1 B 52.6 b B 55.9 b B 60.3 b B 63.8 b B 67.7 b B 68.7 b B 70.1 b B 72.0 B 75.3 B B b or B indicates correction for background noise. B also indicates limit of measurement. Rating according to ISO D ntw (C; C tr) = 54 (-1; -6) db; D ntw + C tr = 48 Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_A_1 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 17 of 22

22 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd Airborne Test No. Test_A_2 Standardized Level Difference according to ISO Field measurements of airborne sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 DnT Curve Ref Curve Shifted Ref Curve Description of test: No.40, Flat 12, 3F Bedroom to No.40, Flat 9, 2F Bedroom Partition: Floor Partition construction: Unknown Source room volume: 17 m 3 Receiver room volume: 33 m 3 Common area: 10 m 2 Freq (Hz) D nt (db) b B 40.9 B 43.7 b 43.9 b b 51.8 B B 50.7 B B 50.8 b B 55.8 b B 57.2 B B 60.6 B B 65.9 B B 69.2 B B 70.8 B B 72.9 B B 77.9 B B 83.3 B B b or B indicates correction for background noise. B also indicates limit of measurement. Rating according to ISO D ntw (C; C tr) = 58 (-1; -6) db; D ntw + C tr = 52 Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_A_2 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 18 of October 2015

23 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Airborne Test No. Test_A_3 Standardized Level Difference according to ISO Field measurements of airborne sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 DnT Curve Ref Curve Shifted Ref Curve Description of test: No.40, Flat 9, Lounge to No.40, Flat 6, 1F Lounge 2F Partition: Floor Partition construction: Unknown Source room volume: 72 m 3 Receiver room volume: 80 m 3 Common area: 23 m 2 Freq (Hz) D nt (db) 35.6 B 38.7 B 39.8 b 42.6 b 43.7 B 45.6 B 49.5 B 53.8 B 56.3 B 58.3 B 60.9 b B 62.0 b B 63.9 b B 64.1 B 64.1 b B 66.9 B B b or B indicates correction for background noise. B also indicates limit of measurement. Rating according to ISO D ntw (C; C tr) = 56 (-2; -6) db; D ntw + C tr = 50 Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_A_3 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 19 of 22

24 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd Airborne Test No. Test_A_4 Standardized Level Difference according to ISO Field measurements of airborne sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 DnT Curve Ref Curve Shifted Ref Curve Description of test: No.38, Flat 6, Lounge to No.38, Flat 4, 1F Bedroom 2F Partition: Floor Partition construction: Unknown Source room volume: 32 m 3 Receiver room volume: 33 m 3 Common area: 13 m 2 Freq (Hz) D nt (db) b b B B B B b B b or B indicates correction for background noise. B also indicates limit of measurement. Rating according to ISO D ntw (C; C tr) = 66 (-2; -8) db; D ntw + C tr = 58 Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_A_4 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 20 of October 2015

25 Report No Olive Villas, Sandown Lane, Liverpool, L15 4HU Airborne Test No. Test_A_5 Standardized Level Difference according to ISO Field measurements of airborne sound insulation between rooms Client: Urban Bubble Ltd Date of test: 9 Oct 2015 Description of test: No.38, Flat 4, Lounge to No.38, Flat 6, 2F Bedroom Partition: Floor Partition construction: Unknown 1F DnT Curve Ref Curve Shifted Ref Curve Source room volume: 96 m 3 Receiver room volume: 52 m 3 Common area: 18 m 2 Freq (Hz) D nt (db) 42.6 B 43.6 B 49.1 b b 50.4 b 50.1 B 51.1 B 51.4 B 53.3 B 54.6 B 56.0 B 58.3 B 60.3 B 61.5 B 61.4 B 62.6 B 67.6 B b or B indicates correction for background noise. B also indicates limit of measurement. Rating according to ISO D ntw (C; C tr) = 58 (-1; -4) db; D ntw + C tr = 54 Pass Evaluation based on field measurement results obtained in 1/3 octave bands by an engineering method Report test no.: Test_A_5 Name of Institute: Miller Goodall Environmental Services Date: 14 October 2015 Signature 21 of 22

26 Olive Villas, Sandown Lane, Liverpool, L15 4HU Urban Bubble Ltd 22 of October 2015