lincoln newby will trust - ribble valley€¦ · lincoln newby will trust proposed residential...

LINCOLN NEWBY WILL TRUST

PROPOSED RESIDENTIAL DEVELOPMENT

LAND OFF CHAPEL HILL, LONGRIDGE

ENVIRONMENTAL NOISE STUDYR1275-REP01-PB12 JULY 2016

RED ACOUSTICS LIMITED Unit 8 Cable Court, Pittman Way, Preston PR2 9YW T 01772 722 182 F 01772 722 451 [email protected] www.redacoustics.co.uk

Registered Company Number 6460126

REPORT DETAILS

Project

Client

Document Reference

Revision

Date Issued

Issued By

Signed

Checked By

Signed

Land off Chapel Hill, LongridgeLand off Chapel Hill, LongridgeLand off Chapel Hill, Longridge

Lincoln Newby Will TrustD & S NewbyWillow Tree BarnAshley LaneGoosnarghPreston PR3 2EE



R1226-REP01-PBR1226-REP01-PBR1226-REP01-PB

A

12 July 2016

Paul Bentley BSc (Hons), MSc, Pg. Dip. IOA AMIOA

Red Acoustics Limited

Unit 8 Cable Court

Pittman Way

Preston PR2 9YW

T: 01772 722182

F: 01772 722451

M: 07740 405006

[email protected]



Unit 8 Cable Court

Pittman Way

Preston PR2 9YW

T: 01772 722182

F: 01772 722451

M: 07740 405006

[email protected]



Unit 8 Cable Court

Pittman Way

Preston PR2 9YW

T: 01772 722182

F: 01772 722451

M: 07740 405006

[email protected]

Simon Webster BEng (Hons) MIOASimon Webster BEng (Hons) MIOASimon Webster BEng (Hons) MIOA

The survey was conducted and this report has been prepared for the private and confidential use of Lincoln Newby Will Trust only and cannot be reproduced in whole or in part or relied upon by any third party for any use whatsoever without the express written authorisation

of Red Acoustics Limited. If any third party whatsoever comes into possession of this report, they rely on it at their own risk and Red Acoustics Limited accepts no responsibility (including in negligence) to any such third party.

PROPOSED RESIDENTIAL DEVELOPMENT - LAND OFF CHAPEL HILL, LONGRIDGE


ENVIRONMENTAL NOISE STUDY - R1275-REP01-PB

mailto:[email protected]

mailto:[email protected]

SUMMARY

Red Acoustics Ltd has been commissioned by Lincoln Newby Will Trust to prepare a study into the noise impact on land off Chapel, Hill Longridge from road traffic noise from Chapel Hill, noise from the nearby Civic Amenity (CA) site and the proposed B2 industrial unit to the rear of the development (Approved under consent 3/2014/0127 issued by Ribble Valley Borough Council). The application seeks to erect four dwellings in a terraced arrangement fronting onto Chapel Hill with the B2 use to the rear and the CA site to the east.

During the preparation of the study a long term unattended monitoring position was established fronting onto Chapel Hill. This position was also supplemented by attended measurements to investigate the noise form the CA site. The study has used this measured data to build a 3D noise model. The model has also used typical measured data for HGV pass-by events and idling for the proposed B2 use as well as the conditioned maximum 50dB LAeq,t noise level stipulated as part of the planning consent.

The model has been used to investigate the impact from the following scenarios:

1. BS4142:2014 impact from the CA site and B2 use.

2. Facade noise levels from road traffic noise, CA site and B2 use during the daytime to determine suitable glazing and ventilation strategy.

3. Garden noise levels from road traffic noise, CA site and B2 use during the daytime.

4. Facade noise levels from road traffic noise during the night-time to determine suitable glazing and ventilation strategy.

The results of the BS4142:204 impact assessment show that the cumulative impact on the proposed development will be no greater than a low impact (<5dB above the typical LA90,t).

Predicted facade noise levels have been used to undertake break-in calculations in accordance with the methodology in BS8233:2014. The results of the noise ingress show that the strategy in the table below can be adopted and the recommended internal noise levels in BS8233:2014 will be achieved.




Floor Elevation Glazing Specification Ventilation Requirement

GroundFront 4/12/6 Acoustic trickle vent

GroundRear 4/12/6 Standard trickle vent

FirstFront 10/12/6 Acoustic trickle vent

FirstRear 4/12/6 Standard trickle vent

Garden noise levels during the daytime from road traffic noise are expected to be less than 55dB LAeq,t. With the inclusion of the industrial uses nearby, Unit 1 garden exceeds the recommended target by 2dB to the Eastern portion of the garden. To mitigate this impact we have recommend these areas are used for planting which will limit the the use of these areas for recreational uses.

The above assumes the inclusion of a 2m high perimeter boundary fence with a surface mass in excess of 10kg/m2. Fences separating the gardens should also be 2m high to the same surface mass.




CONTENTS

1.0 INTRODUCTION 1

2.0 SITE DESCRIPTION & PROPOSED DEVELOPMENT 2

3.0 ENVIRONMENTAL NOISE SURVEYS 3

Figure 3.1: Environmental Noise Survey Positions 3

Figure 3.2: MP1 Survey Data 4

Figure 3.3: MP2 Survey Data 4

Figure 3.4: Road Traffic Noise Calibration Level 5

Table 3.1: Civic Amenity Site Calibration Level 6

Figure 3.5: HGV Passby & Idling Calibration Data 6

4.0 NOISE MODELLING & IMPACT ASSESSMENT 7

Table 4.1: Source Sound Power Levels 8

Table 4.2: Impact Assessment Matrix 8

Table 4.3: Impact Assessment Threshold Values 8

Equation 4.1: On-Time Correction 9

Figure 4.1: HGV Pass-by Event LAeq,t (Centre Unit 4 Garden) 10

Equation 4.2: SEL Equation 10

Equation 4.3: LAeq,t from SEL Equation 10

Table 4.4: Ground Floor Element Sound Insulation Performance Specification 12

Table 4.5: First Floor Element Sound Insulation Performance Specification 13

6.0 CONCLUSIONS 15

APPENDIX A: NOISE SURVEY DETAILS 1




APPENDIX B: GA DRAWINGS AND CADNAA SCREENSHOTS 3

APPENDIX C: BREAK-IN CALCULATIONS 4

APPENDIX D: INSUL DATASHEETS 5




1.0 INTRODUCTION

Red Acoustics Ltd has been commissioned by Lincoln Newby Will Trust to prepare a study into the noise impact on land off Chapel, Hill Longridge from road traffic noise from Chapel Hill, noise from the nearby Civic Amenity (CA) site and the proposed B2 industrial unit to the rear of the development (Approved under consent 3/2014/0127 issued by Ribble Valley Borough Council).

The application seeks to erect four dwellings in a terraced arrangement fronting onto Chapel Hill with the B2 use to the rear and the CA site to the east.

The study has looked at the impact from the surrounding noise generating uses and has developed a mitigation strategy to achieve reasonable standard of acoustic conditions within the dwelling itself and the rear garden.

Adoption of the recommend mitigation will ensure the amenity of the proposed dwellings is protected.




Page 1 of 15

2.0 SITE DESCRIPTION & PROPOSED DEVELOPMENT

The proposed residential development site is located on land off Chapel Hill, Longridge Appendix B presents the proposed layout of the site and drawings used in preparation of this report.

To the South is Chapel Hill, which from our observations is a heavily trafficked road.

To the East of the development site is Longridge Civic Amenity Site operated by SITA on behalf of Lancashire County Council. This facility accepts general household waste from private vehicles.

To the North of the development site is a site with approval for B2 industrial use. The approval compromises a small industrial unit and service yard. The unit is not currently built. Further to the North are more industrial units.




Page 2 of 15

3.0 ENVIRONMENTAL NOISE SURVEYS

Unattended environmental noise survey was carried out between 23rd - 28th June 2016. An attended measurement was carried out on the 28th June 2016 between 12:30 - 14:00 to capture events at the nearby Civic Amenity (CA) site.

Figure 3.1: Environmental Noise Survey Positions

Figure 3.2 presents the summary data for MP1 and Figure 3.2 presents the data for MP2.




Page 3 of 15

Unattended Measurement Position (MP1)

Attended Measurement Position (MP2)

Figure 3.2: MP1 Survey Data

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Figure 3.3: MP2 Survey Data

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Page 4 of 15

Wagon idling at site entrance

General site use:Cars arriving/departingWaste into skips

Skip changeover, site closed

60.1dB LAeq,t

67.7dB LAeq,t

The survey data has been used to calibrate a CadnaA 3D noise model. The model is essentially a snap shot in time and therefore data that represents the highest level of impact has been chosen. Figure 3.4 presents the data used to calibrate the model for road traffic travelling along Chapel Hill.

Figure 3.4: Road Traffic Noise Calibration Level

31.5Hz(dB) 63Hz(dB) 125Hz(dB) 250Hz(dB) 500Hz(dB) 1kHz(dB) 2kHz(dB) 4kHz(dB) 8kHz(dB)A-

WeightedLevel

24/06/201611:55LAeq,5min 68.4

28/06/201606:10:00LAeq,5min 65.7

24/06/201606:00:00LAmax 78.6

24/06/201611:55LAeq,5min 63.4 69.3 61.5 59.5 61.2 63.7 63.1 59.6 52.7

28/06/201606:10:00LAeq,5min 58.1 65.7 65.0 59.6 59.4 63.0 58.8 52.5 47.4

24/06/201606:00:00LAmax 66.6 80.8 68.0 66.9 69.2 75.7 70.8 60.0 51.0

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The sound power of the road source representing Chapel Hill has been calibrated to achieve the levels in Figure 3.4 for daytime (LAeq,t), night-time (LAeq,t) and night-time (LAmax).

Calibration of model for the CA site has also been undertaken. The model has been calibrated to the levels in Table 3.1 below. This is based on the measured Lfeq,t for general site activity (60.1dB LAeq,t) being removed from the site activity when the skip was being removed (67.7dB LAeq,t). The skip changeover activity was by far the loudest event on site. General site activity i.e. vehicles arriving/departing and unloading waste into skips did not affect the measured level at the proposed dwelling house location.




Page 5 of 15

Table 3.1: Civic Amenity Site Calibration Level

Octave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 Pa

31 63 125 250 500 1k 2k 4k 8k

Skip Change Over Level 67.9 71.4 69.4 67.3 63.5 62.8 60.5 55.8 48.9

General Site Activity Level 65.7 68.4 60.3 56.3 56.5 56.5 52.3 46.1 39.7

Corrected Skip Change Over Level 63.9 68.4 68.8 66.9 62.5 61.6 59.8 55.3 48.3

Previously measured data for HGV pass-by events and HGV idling events has also been used in the model. The data was measured at Universal Products Manufacturing Ltd, Kirkham in their service yard and access road. Figure 3.5 presents the measured data the model has been calibrated to.

Figure 3.5: HGV Passby & Idling Calibration Data

6.3 Hz

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Articulated HGV Passby 60.8 66.1 59.4 61.3 63.7 58.1 65.2 62.1 63.6 77.5 64.8 65.7 71.9 68.2 65.2 64.8 59.7 60.1 66.9 67.8 63.7 64.8 67.9 65.5 66.1 62.8 62.3 58.1 55.0 51.9 50.9 48.3 46.8 46.1 41.3 39.0

Articulated HGV Passby 51.7 60.1 57.1 53.0 56.4 59.6 59.1 60.6 76.1 71.2 63.8 69.6 69.1 68.1 70.9 72.3 70.8 70.0 66.2 67.1 71.1 69.5 68.4 66.3 65.8 62.6 60.3 56.7 55.2 52.4 49.4 46.6 43.6 41.2 35.4 29.6

HGV Idling (Nearside) 60.2 57.2 62.4 58.6 61.7 59.7 73.9 71.6 55.6 67.2 69.5 65.5 67.8 63.0 65.6 63.0 66.1 66.2 72.1 72.4 69.6 70.9 72.2 74.3 72.6 69.4 69.6 69.9 65.0 60.5 57.2 54.2 53.7 54.3 52.8 49.0

HGV Idling (Nearside) 68.3 70.4 71.8 69.9 68.6 63.7 68.4 77.6 86.5 67.0 64.3 64.8 67.0 65.2 67.3 68.2 69.3 68.5 69.4 70.6 68.5 70.3 73.4 74.8 71.0 69.6 70.7 70.0 65.0 61.0 58.2 56.5 59.7 58.7 66.5 50.0

HGV Idling (Front - brake pressure buildng up)) 62.2 59.2 59.8 63.1 60.3 54.1 72.6 70.8 55.3 63.3 67.8 60.1 66.3 63.9 60.4 61.7 61.4 65.2 65.9 66.5 68.7 69.4 71.2 70.1 67.4 66.2 64.4 62.8 60.9 54.5 53.7 51.7 49.4 49.4 44.4 37.0

HGV (Front - brake pressure building up) 56.8 56.1 55.5 61.6 54.8 61.1 59.9 71.2 79.0 61.6 61.3 61.9 66.5 65.3 65.2 68.4 66.3 67.3 68.8 77.6 74.5 78.6 74.4 75.7 74.2 72.2 72.1 73.1 66.7 63.3 61.1 58.5 55.8 52.3 50.4 44.9

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4.0 NOISE MODELLING & IMPACT ASSESSMENT

To determine the Impact from noise from various activities CadnaA 3D noise modelling software has been used. The following scenarios have been investigated to determine the impact.

1. BS4142:2014 impact from the CA site and B2 use.

2. Facade noise levels from road traffic noise, CA site and B2 use during the daytime to determine suitable glazing and ventilation strategy.

3. Garden noise levels from road traffic noise, CA site and B2 use during the daytime.

4. Facade noise levels from road traffic noise during the night-time to determine suitable glazing and ventilation strategy.

Scenario 1: BS4142:2104 Impact Assessment from CA Site & Approved B2 Use

The above scenario has been investigated using CadnaA. Table 4.1 presents the source Sound Power Levels used. The levels for the proposed building have been selected to ensure that noise point on the boundary exceeds 50dB LAeq,t as is a requirement of the approved consent.

The assessment is based on the existing background noise data measured during the daytime operational hours. The data is presented in Figure 3.2 above. The typical daytime background has been set as 47dB LA90,t. Using this background noise level, the targets in Table 4.3 have been set based on the assessment matrix presented in Table 4.2.




Page 7 of 15

Table 4.1: Source Sound Power Levels12 3

Noise SourceOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 PaOctave Band Centre Frequency (Hz) Sound Pressure Level dB re: 2x10-5 Pa

Noise Source31 63 125 250 500 1k 2k 4k 8k

CA Site1 99.9 104.4 108.1 111.1 107.7 102.7 99.0 95.1 89.9

HGV Pass-by2 93.8 91.4 91.8 93.4 91.0 90.5 85.8 77.4 69.4

HGV Idling3 104.6 87.8 88.9 91.0 91.9 95.5 92.7 89.1 80.6

Table 4.2: Impact Assessment Matrix

Target Impact

LA90,t > -9.9dBA to ≤ 0.4 dBA No impact

LA90,t ≥ 0.5 dBA to ≤ 4.4dBA Low Impact

LA90,t ≥ +4.5dBA to ≤ 9.4dBA Potential for adverse impact depending on context

LA90,t ≥ +9.5dBA Potential for significant adverse impact depending on context

Table 4.3: Impact Assessment Threshold Values

Target Impact

≤ 47.0dBA No impact

48.0 - 52.0dBA Low Impact

53.0 - 57.0dBA Potential for adverse impact depending on context

≥58.0 Potential for significant adverse impact depending on context

Corrections

Corrections to the above levels have been implemented in the model to account for on-time and acoustic features. The corrections have been calculated as follows:




Page 8 of 15

1 The CA site Sound Power Level includes a correction to the overall A-weighted Broadband Level of 10dB to asses the impact over the total daytime working hours (11hrs). The correction also includes a +6dB feature correction for intermittent bangs. See CA Site Correction below.

2 The HGV pass-by Sound Power includes a correction of -27.3dB to account for 2 movements over the daytime working hours (07:00 - 18:00). See HGV Pass-by Correction below.

3 The HGV idling Sound Power level includes a correction of -22.6dB to correct the the idling HGV (assumed 4 minutes a day) over the rest of the day. See HGV Idling Correction below.

CA Site Correction

A correction for the on time of the skip movements has been undertaken using Equation 4.1 below.

Equation 4.1: On-Time Correction

On-Time Correction = 10 x Log10 (t/T)

where: t is the activity total time in seconds, 900secs

T is the total period time in seconds, 39,600secs

The calculated correction is -16.1dB. To account for the intermittency a feature correction of 6dB has been included at this stage. This equates to a correction of -10.1dB of the result.

HGV Pass-by Correction.

The HGV correction is based on 2 vehicle movements at the approved B2 use per day, based on the pass-by levels (measured in the centre of Unit 4 garden) using the sound power data above. A typical pass-by event when a vehicle is moving at 10kph on site would take 40 seconds. Figure 4.1 presents the pass-by data.




Page 9 of 15

Figure 4.1: HGV Pass-by Event LAeq,t (Centre Unit 4 Garden)

74dBLAeq,40s

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The calculated event LAeq,t is 74.0dB. This can be used to calculate an Sound Exposure Level. The Sound Exposure Level is then used to calculate a LAeq,11hr based on two HGV pass-by events (as assumed in the BDP assessment for B2 use). Equation 4.2 and 4.3 presents the method used to convert the pass-by LAeq to an SEL and then back into a LAeq,t over an 11 hour period with two pass-by events.

Equation 4.2: SEL Equation

SEL = LAeq + 10 x Log10(t)

Where: t is the time of the LAeq in seconds

Equation 4.3: LAeq,t from SEL Equation

LAeq,t = SEL - 10 x Log10(t) + 10 x Log10(n)

Where: t is the total time of the period in question

n is the total number of events in the period.




Page 10 of 15

Using the equations above the calculated LAeq,11hr for the pass-by event was 37.4dB. This equates to a correction of 27.3dB as stated in footnote 2.

HGV Idling Correction.

The idling correction has used Equation 4.1. The calculated correction using a LAeq,11hr time period and assuming for 4 minutes of idling per day is 22.6dB.

Impact Assessment

Figure B3 in Appendix B presents the output from the modelling exercise for scenario 1 based on the assessment matrix in Table 4.3. Based on the output all of the facades except the Eastern facade of Unit 4. However, it should be noted the Eastern Facade of Unit 4 does not have any sensitive windows.

Figure B3 also shows that some of the garden area of Unit 4 has the potential for adverse impact depending in the context. Comparing with the absolute levels for garden noise (including for road traffic from Chapel Hill) it can be seen that the majority of the garden is less than 55dB LAeq,t. Therefore the context of the situation supports that adverse impact is not likely to arise.

No feature correction has been applied to the assessment given the short duration nature of vehicle movement events at the B2 use and CA site when accounting for skip removal activity. As already described, vehicles arriving and departing the CA site are also not noticeable over existing road traffic noise.

Scenario 2: Facade noise levels from road traffic noise, CA site and B2 use during the daytime to determine suitable glazing and ventilation strategy.

To further investigate the impact of the surrounding uses on the proposed dwellings break-in calculations have been carried out using the methodology in BS8233:2014. The purpose of the break-in calculation was to investigate required glazing and ventilation strategy for the dwellings based on all noise sources operating.

The recommended target levels for the daytime for habitable rooms is less than or equal to 35dB LAeq,t.




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Appendix C presents the break-in calculations for the study. The calculations has used a the worst case facade level as the source for daytime LAeq,t. This includes contributions from road traffic, the CA site and the proposed B2 use.

Figure B1 in Appendix B presents a noise map with the recommended glazing and ventilation strategy to achieve the internal target noise levels. Table 4.4 presents the minimum glazing and ventilation element performance as well as the predicted performance using INSUL for a standard cavity masonry construction.

Table 4.4: Ground Floor Element Sound Insulation Performance Specification

ElementOctave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)

Element31 63 125 250 500 1k 2k 4k

Glazing SRI 11.0 17.0 19.0 17.0 32.0 37.0 38.0 40.0

Standard Trickle Vent Dne 27.0 28.4 27.9 30.8 30.5 29.0 33.7 33.7

Acoustic Trickle Vent Dne 27.0 30.0 34.0 40.0 39.0 42.0 49.0 43.0

External Wall SRI 45.0 47.0 48.0 44.0 46.0 54.0 63.0 71.0

To achieve the glazing specification a configuration of 4mm float, 12mm air gap 6mm float will be acceptable.

A standard window trickle ventilator such as the Titon Trim vent will be acceptable on the rear elevations with a AERECO EHA2 vent acceptable on the front elevation.

Details of the proposed glazing and ventilation elements should be submitted to Red Acoustics in order to confirm compliance with the above specification.

The above specification is also based on the perimeter of the rear gardens being provided with a 2m high barrier with a surface mass of at least 10kg/m2.

Scenario 3: Garden noise levels from road traffic noise, CA site and B2 use during the daytime

Figures B4 and B5 in Appendix B show the predicted garden levels in comparison to the requirements of WHO 1999 of 55dB LAeq,t. With just road traffic noise the gardens are predicted to achieve less than 55dB LAeq,t. With the addition of the industrial noise a small portion of Unit 4 exceeds 55dB LAeq,t.




Page 12 of 15

These predictions assume for a 2m high perimeter fence (surface mass should exceed 10kg/m2) and 2m high separating fences between gardens to the same surface mass. A higher fence is unlikely to be allowed so therefore we would recommend this area of the garden is provided with heavy planting in order to restrict the use of the garden to areas where noise levels are 55dB LAeq,t or less.

Scenario 4: Facade noise levels from road traffic noise during the night-time to determine suitable glazing and ventilation strategy

To investigate the impact of the road traffic uses on the proposed bedrooms of the dwellings break-in calculations have been carried out using the methodology in BS8233:2014. The purpose of the break-in calculation was to investigate the required glazing and ventilation strategy.

The recommended target levels for the night-time for habitable rooms is less than or equal to 30dB LAeq,t and is less than or equal to 45dB LAmax.

Appendix C presents the break-in calculations for the study. The calculation has used a the worst case facade level as the source for night-time LAeq,t and LAmax. It should be noted that the night-time maximum noise levels does not drive the facade design as it does not exceed the LAeq,t by more than 15dB.

Figure B2 in Appendix B presents a noise map with the recommended glazing and ventilation strategy. Table 4.5 presents the minimum glazing and ventilation element performance as well as the predicted performance using INSUL for a standard cavity masonry construction.

Table 4.5: First Floor Element Sound Insulation Performance Specification

ElementOctave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)Octave Band Centre Frequency (Hz) Sound Insulation Value (SRI or Dne)

Element31 63 125 250 500 1k 2k 4k

Glazing Type 1 (4-12-6) SRI 11.0 17.0 19.0 17.0 32.0 37.0 38.0 40.0

Glazing Type 2 (10-12-6) SRI 16.0 21.0 26.0 27.0 34.0 37.0 38.0 38.0

Standard Trickle Vent Dne 27.0 28.4 27.9 30.8 30.5 29.0 33.7 33.7

Acoustic Trickle Vent Dne 27.0 30.0 34.0 40.0 39.0 42.0 49.0 43.0

External Wall SRI 45.0 47.0 48.0 44.0 46.0 54.0 63.0 71.0




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To achieve the glazing specification a configuration for type 1 a 4mm float, 12mm air gap 6mm float will be acceptable. To achieve the glazing specification for type 2 glazing a 10mm float, 12mm air gap 6mm float will be acceptable.

A standard window trickle ventilator such as the Titon Trim vent will be acceptable on the rear elevations with a AERECO EHA2 vent acceptable on the front elevation.

Details of the proposed glazing and ventilation elements should be submitted to Red Acoustics in order to confirm compliance with the above specification.




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6.0 CONCLUSIONS

An assessment of the impact from road traffic noise, the CA site and the approved B2 use at the site off Chapel Hill, Longridge.

The assessment has demonstrated that the site can be developed for residential accommodation and be adequately protected from existing environmental noise and future predicted environmental noise from the B2 use.

Implementation of the recommended glazing and ventilation strategies will ensure internal noise levels do not exceed the recommended internal requirements.

The impact from the industrial uses has also been assessed in accordance with the guidance in BS4142:2014. Based on the assessment none of the habitable facades exceed an impact of low and all the gardens except a portion of Unit 4 are low.

The portion of Unit 4 to the east is predicted to be within potential adverse impact depending on context band. When looking at the context the areas only marginally exceeds 55dB LAeq,t with all noise sources. To off set this impact we have recommended that the area is used for planting only to limit its use.




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APPENDIX A: NOISE SURVEY DETAILS

Location

Land off Chapel Hill, Longridge

Survey Dates

23rd - 28th June 2016 (unattended)

28th June 2016 (attended)

Weather

Forecast: Dry with wind speeds <5m/s.

Personnel Present During Measurements

John Whittle AMIOA




Instrumentation

Kit NoEquipment Description

Type Number

ManufacturerSerial

Number

Date of Last

Calibration

Calibration Certificate

Number

Calibration Due

RED 05

(MP1)

Sound Level Meter

CR:171B Type 1

Cirrus G056965 28-Apr-15 228143 27-Apr-17

RED 05

(MP1)

Sound Calibrator

CR:515 Type 1

Cirrus 59153 10-May-16 02691/2 05-May-17RED 05

(MP1)Outdoor Mic

CapsuleMK: 224 Cirrus 20044889 28-Apr-15 - 27-Apr-17

RED 09 (MP2)

Sound Level Meter

Type 140 Type 1

Norsonic 1402793 12/05/15 18739 12/05/17

RED 09 (MP2)

Preamplifier Nor 1209 Norsonic 12152 12/05/15 18739 12/05/17RED 09 (MP2) Microphone

CapsuleNor 1225 Norsonic 72874 12/05/15 18738 12/05/17

RED 09 (MP2)

Sound Calibrator

Type 1251 Class 1

Norsonic 34390 09/04/15 2220155245 09/04/16

Methodology

Before and after the measurements the sound level meters were check calibrated to an accuracy of ±0.3dB using their associated Class 1 Calibrators. No drift in the instruments’ sensitivities were noted across any of the survey periods.

Calibration Certificates

Copies of all calibration certificates are kept on file by Red Acoustics Ltd and can be supplied if requested.




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