nuig student accommodation, phase 2 · 2019-02-28 · report author: irene sofia rodriquez beng...

Allegro Acoustics Limited, C1 South City Business Park, Tallaght, Dublin 24

Tel: +353 (0) 1 4140485 www.allegroacoustics.ie

www.allegroacoustics.ie

NUIG Student Accommodation, Phase 2

Upper Newcastle, Galway

Noise Impact Assessment

And Façade Noise Assessment

27 February 2019

Report Author: Irene Sofia Rodriquez

Report: DC1688-01

http://www.allegroacoustics.ie/

Page | 2 DC1688-01: NUIG Student Accommodation, Phase 2 27/02/2019 Noise Impact Assessment and Façade Noise Assessment

EXECUTIVE SUMMARY

Allegro Acoustics was retained by the National University of Ireland, Galway to complete a Noise Impact Assessment and a Façade Noise Assessment for the proposed NUIG Student Accommodation, Phase 2 at Upper Newcastle, Galway.

The purpose of these assessments is to:

• Determine the potential noise impact from students gathering in the Courtyards of the Student Accommodation and from M&E Plant equipment upon nearby noise sensitive receptors;

• Determine the Façade noise levels for the purposes of specifying performance criteria.

The proposed Student Accommodation is surrounded by Corrib Village student accommodation and a number of residential estates along the Upper Newcastle road. This Student Accommodation facility has external Courtyards as shown in Figure A below.

Figure A: Drawing showing the proposed facility with the external Courtyards outlined in orange and monitoring locations, N1 and N2 outlined in red.

Figure B: Noise monitoring locations N1, N2 and N3.


Noise Impact Assessment

Existing noise levels at surrounding residential estates were measured at monitoring locations N1 and N2 to determine the background noise levels at the nearest sensitive receptors to the proposed development. The noise monitoring locations N1 and N2 are shown in Figure B above.

During the day time period an average noise level of 41dB LA90 was measured at location N1 and an average noise level of 38dB LA90 was measured at location N2. During the night time period, an average noise level of 38dB LA90 was measured at location N1 and an average noise level of 38dB LA90 was measured at location N2. Detailed measured noise levels are presented in Section 2.2 of this report and also in Appendix A.

In order to determine the noise impact from the Student Accommodation, predicted noise levels due to the proposed facility were calculated. These calculations were used to predict the noise levels at the nearest residences N1 and N2 to the proposed Student Accommodation due to the combination of externally located M&E plant equipment and potential student activity in the external Courtyards. The noise levels predicted by the noise level calculations, without any attenuation applied to M&E plant equipment, are in excess of the existing noise levels at the closest residential buildings.

Should a Heat Pump which may be used to achieve Nearly Zero Energy Building (NZEB) standards be installed which is similar in specification to that assumed in this report, it is recommended to attenuate this by 5dB so that the resulting Sound Power Level does not exceed 82.7dB LwA. Once this is attenuated by 5dB, the resulting noise levels are predicted to be 35.9dB LAeq and 31.4dB LAeq

respectively at locations N1 and N2; which represent the closest residential receptors to the Student Accommodation. These predicted noise levels are below the average measured background noise levels at the closest residential buildings. In addition, the predicted noise levels are below the lowest 39.5dB LAeq value measured during night time at location N1 and the 39dB LAeq value measured during night time at location N2. These predicted noise levels are also below the 45dB LAeq night time noise limit value as recommended by the EPA [1] and WHO [2].

Hence, it is concluded that once the recommended attenuation measures are implemented, the proposed Student Accommodation facility will not have any significant negative impact upon the nearest residences with respect to noise.

Façade Noise Assessment

This report also includes a Façade Noise Assessment to conclude acoustic performance specification for the façade. In order to determine the ambient noise level at the site of the proposed student accommodation, existing noise levels were measured at the site of the proposed development (location N3).

The noise level at location N3 was measured to be 43dB LAeq during the day time period and 41dB LAeq during the night time period. The measured noise levels are presented in Section 2.2 of this report and also in Appendix A.

Internal Noise Level criteria were set for this facility using guidance outlined in BS8233: 2014, Guidance on sound insulation and noise reduction for buildings [7]. The Airborne Sound Insulation Performance (dB Rw) for the façade structure to achieve these criteria was calculated for day and night time using the measured noise data at N3. It is concluded that the façade must achieve a minimum of 17dB Rw. This can be typically achieved using standard double glazing and a standard façade construction. High performance acoustic glazing and trickle ventilators are therefore not required.


REPORT CONTROL

Document Title: Noise Impact Assessment and Façade Noise Assessment

Project: NUIG Phase 2 Student Accommodation

Client: National University of Ireland, Galway

Job Number: DC1688-01

File Origin: Z:\Allegro Acoustics\Allegro Acoustics Live\Projects\DC1550 to DC1900\DC1688\Reports

Report Author: Irene Sofia Rodriquez BEng MEng MIEI

Signed:

Date: 27 February 2019

Issue Date Status Checked By Signed

1 31/05/2018 DRAFT Stephen Kearney BE MIEI AMIOA

2 06/06/2018 DRAFT David Cawley BE MSc CEng MIEI MIOA

3 27/02/2019 FINAL David Cawley BE MSc CEng MIEI MIOA

4


TABLE OF CONTENTS

1 INTRODUCTION ............................................................................................................................... 7

2 BASELINE NOISE SURVEY................................................................................................................. 8

2.1 Methodology ........................................................................................................................... 8

2.2 Environmental Noise Monitoring ............................................................................................ 9

3 NOISE IMPACT ASSESSMENT .......................................................................................................... 9

3.1 Noise Impact Assessment Criteria .......................................................................................... 9

3.1.1 Guidance Note for Noise (NG4) (EPA 2016) .................................................................. 10

3.1.2 Environmental Noise Guidelines for the European Region (WHO 2018) ..................... 11

3.2 Noise Level Calculations ........................................................................................................ 11

3.2.1 Mechanical and Electrical (M&E) Plant Equipment ...................................................... 11

3.2.1.1 Generator Plantroom ................................................................................................ 12

3.2.2 Noise Level Calculation Assumptions............................................................................ 12

3.3 Predicted Noise Levels – No Attenuation ............................................................................. 13

3.4 Noise Attenuation ................................................................................................................. 13

3.5 Predicted Noise Levels – With Attenuation .......................................................................... 14

3.6 Discussion .............................................................................................................................. 14

3.6.1 Guidance Note for Noise (NG4) .................................................................................... 14

3.6.2 Environmental Noise Guidelines for the European Region (WHO 2018) ..................... 14

3.6.3 Comparison with Measured Noise Levels ..................................................................... 14

4 FAÇADE NOISE ASSESSMENT ........................................................................................................ 15

4.1 Internal Ambient Noise Level Criteria ................................................................................... 15

4.2 Façade Design ....................................................................................................................... 15

5 CONCLUSION ................................................................................................................................. 16

5.1 Noise Impact Assessment ..................................................................................................... 16

5.2 Façade Noise Assessment ..................................................................................................... 17

6 REFERENCES .................................................................................................................................. 17

APPENDICES

Appendix A - Noise Monitoring Data

Appendix B - Calibration Certification

Appendix C - Noise Level Calculations


GLOSSARY OF TERMINOLOGY

dB(A): Decibels measured on a sound level meter incorporating a frequency weighting (A weighting)

which differentiates between sound of different frequency (pitch) in a similar way to the human ear.

Measurements in dB(A) broadly agree with human perception of loudness whereby a 10dB increase /

decrease is generally perceived as a doubling / halving in loudness respectively.

LAeq, Equivalent Continuous A-weighted Sound Level: The continuous steady noise level, which would

have the same total A-weighted acoustic energy as the real fluctuating noise measured over the same

period of time.

LA90: The A-weighted noise level that is equalled or exceeded for 90% of the measurement period. This is typically used to indicate the background noise level at a location.

LA10: The A-weighted noise level that is equalled or exceeded for 10% of the measurement period.

LAmax, Maximum A-weighted instantaneous noise level that is measured throughout a noise

measurement. In the case of road traffic for example, the LAmax is representative of the noise level due

to a passing vehicle at the closest / loudest point.

NR, Noise Rating: This indicator refers to the constant background noise level in a room. This a dB

value and is based on a set of ISO derived NR Curve values. This indicator is commonly used to set a

limit for or assess air management system noise in a building; which emanates a constant sound.

Relationship between LAeq and NR: LAeq ≈ NR + 5

Rw, Sound Reduction Index: This is a measure of sound insulation provided by an individual element

(such as a specific wall partition, door or window) when the element is tested in an acoustic testing

laboratory. The Rw must be determined by testing in accordance with ISO 10140-1.

Ctr: This is a correction applicable to sound insulation performance indicators where the dominant

noise source is road traffic.

DnT,w, Weighted Standardised Level Difference: This is a measure of the level of airborne sound

insulation provided by the built element between two rooms whereby higher values represent better

airborne sound insulation. The DnT,w performance is verified by carrying out airborne sound insulation

testing as outlined in ISO 16283-1.

RT, Reverberation Time: The Reverberation Time or RT is a measure of “echo” in a room and is defined

as the length of time taken for a sound to drop by 60dB in a room. This is measured by generating a

loud sound in a room and measuring the first 20dB or 30dB of decay across the relevant frequency

range. Typically, rooms designed for speech exhibit shorter RT values to accommodate a sharpening

of syllabic and phonetic sounds. Rooms designed for music tend to exhibit longer RT values to suit

musical ambience.

NSL: Noise Sensitive Location; in the case of this assessment, the Noise Sensitive Location is representative of the nearest residential receptors to the proposed student accommodation.

1/3rd Octave Band: For simplicity, the frequency spectrum is sub divided into bands of one third of an

octave each. An octave is taken to be the frequency interval, the upper limit of which is twice the

lower limit (in Hertz).


1 INTRODUCTION

Allegro Acoustics was retained by the National University of Ireland, Galway to complete a Noise Impact Assessment and a Façade Noise Assessment for the proposed NUIG Student Accommodation – Phase 2 facility at Upper Newcastle, Galway.

The purpose of these assessments is to:

• Determine the potential noise impact from the Student Accommodation due to students potentially gathering in the external Courtyards of the Student Accommodation and M&E Plant equipment upon nearby noise sensitive receptors;

• Determine the Façade noise levels for the purposes of specifying acoustic performance criteria for the facade.

The proposed Student Accommodation is surrounded by Corrib Village student accommodation and a number of residential estates along the Upper Newcastle road. The facility has two external Courtyards as shown in Figure 1 below.

In order to determine the noise impact due to the Student Accommodation, predicted noise levels due to the proposed facility were calculated. These calculations were used to predict the noise levels at the nearest residences to the proposed Student Accommodation due to the combination of externally located M&E plant equipment and potential student activity in the Courtyards.

The impact upon nearby residential receptors has been assessed by comparing the predicted noise levels due to the Student Accommodation facility with the existing noise environment at these receptors and with recognised noise limits as set out by the Environmental Protection Agency [1] and the World Health Organisation [2].

Figure 1: Drawing showing the proposed student accommodation facility with the Courtyards outlined in orange and monitoring locations, N1 and N2 outlined in red.

This report also details the acoustic criteria for the building envelope of NUIG Student Accommodation – Phase 2. This includes façade design recommendations to achieve the acoustic criteria outlined in the standard BS8233: 2014, Guidance on sound insulation and noise reduction for buildings [7]. This assessment takes into account the measured noise levels at the site of the proposed student accommodation.


2 BASELINE NOISE SURVEY

2.1 Methodology

Noise monitoring was carried out at locations N1 and N2 as shown in Figure 2 below to determine existing noise levels at the nearest residential estates to the proposed facility. Noise monitoring was also carried out at the location N3 as shown in Figure 2 below to determine the level of environmental noise at the site of the proposed development during day and night time hours. The noise measurement locations are detailed in Table 1 and outlined in Figure 2 below.

Location Receptor Type Measurement Description

N1 Residential - NSL 24 hours

N2 Residential - NSL 30 minutes day and 30 minutes night

N3 Onsite 30 minutes day and 30 minutes night

Table 1: Description of noise measurement locations.

Figure 2: Noise monitoring locations N1, N2, N3.

Cognizance was paid to the methodologies as outlined in Guidance Note for Noise: License Applications, Surveys and Assessments in Relation to Scheduled Activities (NG4) [1] and ISO 1996 Acoustics – Description and Measurement of Environmental Noise [3].

The measurements at location N1 were recorded using a Cirrus Optimus Sound Level Meter (SLM). The measurements at locations N2 and N3 were made using a Bruel & Kjaer 2250 Sound Level Meter (SLM). Both of these sound level meters measure simultaneously in every 1/3rd octave frequency band from 12.5Hz to 20 kHz. The Sound Level Meters were calibrated before and after the noise survey commenced using a Bruel and Kjaer Type 4231 acoustic calibrator. Both Sound Level Meters are Class 1 instruments in accordance with IEC 61672 regulations. The Time Weighting used was Fast and the Frequency Weighting was A-weighted as per IEC 61672. Calibration certificates for all sound monitoring equipment are included in Appendix B.


2.2 Environmental Noise Monitoring

The existing noise levels as measured at N1, N2 and N3 (Figure 2 above) are presented in Table 2 below. The day and night values given are the average values for the LAeq and the LA90 (representative of the background noise level) during day and night time periods. These periods are defined as follows in NG4 [1]:

• Day: 7am to 7pm

• Night: 11pm to 7am

The single figure day and night time values are presented in Table 2 below. A detailed table of measured noise levels is presented in Appendix A.

Location Description Period Measurement Period dB LAeq dB LA90

N1 (24 Hour

Measurement)

Residential Dwelling

Day 07:00 – 19:00 50.77* 41.09*

Night 23:00 – 07:00 46.40* 38.03*

N2 Residential

Dwelling

Day 17:14 – 17:44 46.51 38.32

Night 23:40 – 00:10 39.0 37.77

N3 Onsite

Day 18:01 – 18:31 42.55 39.16

Night 23:02 – 23:32 40.70 36.66

Table 2: Summary of Noise Monitoring Survey Results.

* Average LAeq,30mins and LA90,30mins measured over the period indicated – Reference Appendix A for further detail.

3 NOISE IMPACT ASSESSMENT

3.1 Noise Impact Assessment Criteria

Predicted noise levels resulting from the Student Accommodation are presented in this report and compared with both existing noise levels measured at the nearest residential locations and with the noise limits outlined in Guidance Note for Noise (NG4) (EPA 2016) [1] and Guidelines for Community Noise WHO [2]. In order to relate the noise level values in this report to real life noise events, an excerpt has been taken from NG4 [1] and is presented in Figure 3 below. Figure 3 shows the noise level for normal, everyday events.


Figure 3: Noise levels attributable to everyday events as taken from NG4 [1].

3.1.1 Guidance Note for Noise (NG4) (EPA 2016)

In concluding an appropriate noise limit value for noise generated at the proposed Student Accommodation facility, reference is made to Guidance Note for Noise: License Applications, Surveys and Assessments in Relation to Scheduled Activities (NG4) [1]. The most relevant noise limit criterion as outlined in NG4 [1] is considered to be the night time noise criteria as this is the most stringent criteria. This criterion is considered to be applicable at the nearest noise sensitive receptor to the Student Accommodation and is outlined as follows:

• Night-time Noise Criterion, dB LAeq,T (23:00 to 07:00hrs): 45dB


Figure 4: Extract from Guidance Note for Noise (NG4) [1] outlining a night time noise limit of 45dB at the nearest noise sensitive location.

3.1.2 Environmental Noise Guidelines for the European Region (WHO 2018)

The following guidelines are outlined in the World Health Organisation document Environmental Noise Guidelines for the European Region (2018) [2]:

“During daytime, few people are highly annoyed at LAeq levels below 55dB(A) and few are moderately annoyed at LAeq levels below 50dB LAeq. Sound levels during the evening and night should be 5-10dB lower than during the day”.

This indicates that during night time hours, noise from the Student Accommodation facility generating sound levels of 45dB LAeq and below, are unlikely to result in noise annoyance.

3.2 Noise Level Calculations

Externally located M&E plant equipment and potential student activity in the Courtyards were assessed to predict the resulting noise impact at the nearest residences to the proposed Student Accommodation facility. Allegro Acoustics calculated the M&E plant equipment noise level plus the likely noise level due to 60 students gathering in the external Courtyards of the proposed facility, with 50% of these talking simultaneously.

3.2.1 Mechanical and Electrical (M&E) Plant Equipment

The full extent of the externally located M&E Plant Equipment for this project has not been finalised at the time of this assessment. Allegro Acoustics has therefore estimated the level of externally located M&E Plant Equipment based on similar sized student accommodation facilities. This includes one Heat Pump which may or may not be installed to achieve NZEB Standards. Allegro Acoustics has estimated that the following items of M&E Plant Equipment will be installed for this development:


• 60 nr. standard bathroom fans;

• 1 nr. Heat Pump;

• 2 nr. AC Units.

Sound Power data for each item of M&E noise generating plant is displayed in Table 3 below. These items of M&E noise generating plant equipment are considered in the noise level calculations as operating at full capacity.

3.2.1.1 Generator Plantroom

As advised by J.V. Tierney & Co., the M&E plant items include a Generator located at the North side of the development. However, the Generator is a life safety Generator and will only be operating as a life safety Generator and during routine maintenance and testing once a month. Therefore, in normal circumstances the Generator will not be operational. The Generator will be enclosed within a blockwork structure with Louvers for ventilation. The following recommendations are made relative to noise control for the Generator Plantroom:

• Attenuation of the Generator (enclosure, louvres and built structure) must ensure that the noise level at the façade of the nearest student living space does not exceed 55dB LAeq,T. Recommended suppliers of suitable Louvre solutions are as follows:

o Acoustic Louvres: Caice UK: https://www.caice.co.uk/wp-content/uploads/2018/09/Caice-Acoustic-Louvre-Brochure.pdf

o Acoustic Louvres: QEF: http://www.qefltd.ie/

o Acoustic Louvres: Ventac Group: http://www.ventac.com/

• Generator testing must only be carried out during day time hours.

3.2.2 Noise Level Calculation Assumptions

The following assumptions were implemented in the noise level calculations:

• Noise source data for each student talking was taken from the SoundPLAN V7.3 noise source library and the data for “Speaking Normal” was used. This gives each person talking a Sound Power Value of 65dB Lw(A).

• As there are no direct lines of sight from the Courtyards of the proposed Student Accommodation to the noise sensitive location N2 (Corrib Village) as shown in Figure 1 above, the Sound Power Level from each student was reduced by 6dB for the noise level calculations at N2. This reduction accounts for the blocked line of sight. Therefore, the Sound Power Level attributed to each person talking is 59dB Lw(A) for the noise level calculations at location N2 as shown in Appendix C. This 6dB reduction was not applied to calculations at noise sensitive location N1.

• Noise data for each item of plant used in the Noise Calculations were based on data sheets provided by Vent Axia and Mitsubishi. Sound Power data for each item of plant are displayed in Table 3 below.

https://www.caice.co.uk/wp-content/uploads/2018/09/Caice-Acoustic-Louvre-Brochure.pdf

https://www.caice.co.uk/wp-content/uploads/2018/09/Caice-Acoustic-Louvre-Brochure.pdf

http://www.qefltd.ie/

http://www.ventac.com/


Equipment Code Sound Power, dB Lw, per Octave Sound Power Level

dB LwA 125 250 500 1k 2k 4k 8k

Bathroom Fan – Vent Axia Roof Fan Model TX9 - Exhaust

65.7 61.2 56.8 55.5 52.3 46.6 41.7 60.58

AC Unit – Mitsubishi PUHZ RP100VKA - Cooling

59.9 56.9 53.9 51.9 47.9 41.9 36.9 56.76

AC Unit – Mitsubishi PUHZ RP100VKA - Heating

61.9 60.9 56.9 53.9 49.9 43.9 36.9 59.35

Heat Pump – Mitsubishi Climaveneta AW-HT/LN-CA-E/0524

89 88 86 83 78 71 65 87.74

Table 3: M&E Equipment list and associated acoustic data for the externally located M&E plant as currently assumed in the noise level calculations for the proposed Student Accommodation.

3.3 Predicted Noise Levels – No Attenuation

The predicted Sound Pressure Levels at the noise sensitive receptors N1 and N2 due to the proposed Student Accommodation are outlined in Table 4 below. A detailed table of results is available to view in Appendix C.

Noise source Location Predicted Sound Pressure Level LAeq,total [dB]

M&E Plant equipment + Students N1 39.2

N2 35.3

Table 4: Predicted Sound Levels at locations N1 and N2 due to the proposed Student Accommodation with no attenuation measures applied.

3.4 Noise Attenuation

Based on the results outlined in Table 4 above, should the Heat Pump which may be used to achieve Nearly Zero Energy Building (NZEB) standards be installed, Allegro Acoustics recommends noise control engineering solutions which provide an Insertion Loss of 5dB as outlined in Table 5 below. Attenuated Sound Power Levels are displayed in Table 5 below. Where M&E Plant Equipment which differs to that outlined in Table 5 below is implemented, the Sound Power Levels from this equipment must not exceed the Attenuated Sound Power Levels as outlined in Table 5.

Equipment Code Sound Power Level

dB LwA

Insertion Loss

Required dB

Attenuated Sound Power

Level

dB LwA

Bathroom Fan – Vent Axia Roof Fan Model TX9 - Exhaust

60.58 0 60.58

AC Unit – Mitsubishi PUHZ RP100VKA - Cooling

56.76 0 56.76

AC Unit – Mitsubishi PUHZ RP100VKA - Heating

59.35 0 59.35

Heat Pump – Mitsubishi Climaveneta AW-HT/LN-CA-E/0524

87.74 5 82.74

Table 5: M&E Equipment list and associated acoustic data for the roof plant with attenuation measures applied.


3.5 Predicted Noise Levels – With Attenuation

The predicted Sound Pressure Levels at the noise sensitive receptors N1 and N2 due to the proposed Student Accommodation, once the 5dB attenuation measure has been applied, are outlined in Table 6 below. A detailed table of Predicted Sound Pressure Levels is presented in Appendix C.

Noise source Location Predicted Sound Pressure Level LAeq,total [dB]

Plant equipment + Students N1 35.9

N2 31.4

Table 6: Predicted Sound Levels at locations N1 and N2 due to the proposed Student Accommodation once the 5dB attenuation measure has been applied to the Heat Pump.

3.6 Discussion

3.6.1 Guidance Note for Noise (NG4)

By viewing the predicted noise levels presented in Table 6 above, it can be seen that the predicted noise levels of 35.9dB and 31.4dB LAeq at the nearest façade of the residences at locations N1 and N2 are lower than the night time noise limit value of 45dB LAeq as outlined in to Guidance Note for Noise (NG4) [1]. The proposed Student Accommodation facility is therefore considered to comply with this EPA guideline document [1].

3.6.2 Environmental Noise Guidelines for the European Region (WHO 2018)

The World Health Organisation document Environmental Noise Guidelines for the European Region (2018) [2] as discussed in Section 3.1.2 above, indicates that during day and night time hours, sound levels of below 45dB LAeq are unlikely to result in noise annoyance. The predicted noise levels of 35.9dB and 31.4dB LAeq at the nearest façade of the residences at locations N1 and N2, are significantly lower than 45dB LAeq and are therefore considered unlikely to result in noise annoyance.

3.6.3 Comparison with Measured Noise Levels

The predicted noise levels with attenuation measures applied as calculated in Section 3.5 above have been compared with the background noise levels dB LA90 as measured at N1 and N2. This is shown in Table 7 below.

Receiver

Predicted Noise Levels from proposed Student Accommodation facility

Existing Measured Background Noise Levels

Below Existing Background

Measured Noise Levels

M&E Plant equipment + Students

Day time Night time

Attenuated dB LAeq,total Average dB LA90 Average dB LA90

N1 35.9 41.1 38.0 YES

N2 31.4 38.3 37.8 YES

Table 7: Comparison of predicted noise levels with the existing day and night time noise levels as measured.

The predicted noise levels at N1 and N2 due to the proposed Student Accommodation facility are not predicted to exceed background noise levels, at the nearest noise sensitive receptors.

In addition, the noise levels predicted at N1 and N2 are also lower than the existing lowest dB LAeq values measured during night time at N1 and N2 (39.5dB LAeq and 39dB LAeq respectively).


It is therefore concluded by Allegro Acoustics that noise from the Student Accommodation is likely to be inaudible at the nearest surrounding residences due to the existing noise environment in this suburban area.

4 FAÇADE NOISE ASSESSMENT

4.1 Internal Ambient Noise Level Criteria

The Internal Ambient Noise Level Criteria values which must be achieved for spaces throughout the facility are detailed in Table 8 below. The major sources of noise affecting noise levels internally in the facility have been identified as the following:

• Mechanical and Electrical Services and Plant Noise;

• Intrusive noise due to road traffic.

The building façade must be designed to provide sufficient sound insulation so that Intrusive Noise levels do not exceed the criteria values (dB LAeq) outlined in Table 8 below.

Space Intrusive Noise Reference Document

dB LAeq *GP: Good Practice

Cluster Common Rooms / Kitchens ≤35

BS8233 [7] Bedrooms and Studios (Daytime) ≤35

Bedrooms and Studios (Night time) ≤30

Stairwells and Corridors ≤45 BB93 [8]

Table 8: Noise Rating and Intrusive Noise Level criteria.

Natural Ventilation

The following is outlined in BS8233 [7] in reference to internal noise levels with windows opened to allow for natural ventilation:

Note 7 (pg 25): Where development is considered necessary or desirable, despite external noise levels above WHO guidelines, the internal target levels may be relaxed by up to 5dB and reasonable conditions still achieved.

Hence, a 5dB relaxation can be applied to the dB LAeq values outlined in Table 8 in the scenario whereby the room is naturally ventilated. This will result in the criteria level for Common Rooms being ≤40dB LAeq instead of ≤35dB LAeq and Bedrooms being ≤35dB LAeq instead of ≤30dB LAeq in the natural ventilation scenario.

4.2 Façade Design

Design recommendations for the façade are outlined in this section which achieve the acoustic criteria values (dB LAeq Intrusive Noise) outlined in Section 4.1 above.

The acoustic performance dB Rw to be achieved by the façade of the proposed Student Accommodation has been calculated as follows:

𝑅𝑊 = 𝐿𝑜𝑢𝑡𝑠𝑖𝑑𝑒 − 𝐿𝑖𝑛𝑠𝑖𝑑𝑒 + 6𝑑𝐵

where Loutside is the dB LAeq noise level as measured onsite at the location N3, Linside is the dB LAeq acoustic criteria outlined in Section 4.1 above, 6dB is a correction factor that takes into account reverberation.


Table 9 below shows the required performance dB Rw values calculated with the methodology outlined above:

Location Description Period dB Loutside (LAeq) dB Linside (LAeq) dB Rw

N3 Onsite Day 43 35 14

Night 41 30 17

Required performance 17

Table 9: Airborne Sound Insulation performance dB Rw in relation to the façade of the proposed Student Accommodation.

The dB Rw value concluded in Table 9 above for the façade can be achieved using a standard double glazing and a standard façade construction. High performance acoustic glazing and trickle ventilators are not required.

A sample glazing specification is shown in Table 10 below:

Sound Insulation Requirement of

Glazed Element Glazing Description

≥17 dB Rw

Standard Double Glazing

Example Product:

4mm / 6 - 16mm Airgap / 4mm Pilkington Insulating Glass Unit

Performance: 29dB Rw (-1; -4) http://www.pilkington.com/en/global/products/product-categories

Table 10: Sample Glazing specification for spaces throughout.

5 CONCLUSION

5.1 Noise Impact Assessment

Following an assessment of the potential impact of the environmental noise emanating from the Student Accommodation facility the following conclusions are made:

• The noise levels predicted by the Noise Level Calculations, without any attenuation, are in excess of the existing noise levels measured at the closest residential buildings.

• As detailed in Section 3.4 above, should a Heat Pump which may be used to achieve Nearly Zero Energy Building (NZEB) standards be installed which is similar in specification to that assumed in this report, it is recommended to attenuate this by 5dB so that the resulting Sound Power Level does not exceed 82.7dB LwA.

• The noise levels with attenuation measures in place are predicted to be below the relevant noise limit values as recommended by the EPA and WHO and the existing noise levels at the closest residential buildings.

Hence, it is concluded that once the recommended attenuation measures are implemented, the proposed Student Accommodation facility is not predicted to have any significant negative impact upon the nearest residences to the proposed Student Accommodation with respect to noise.


5.2 Façade Noise Assessment

Following an assessment of the façade noise levels for the proposed Student Accommodation facility, the following conclusions are made:

• Day and night time noise levels measured at the location of the proposed Student Accommodation (N3) and Internal Noise criteria as set for this facility using guidance outlined in BS8233: 2014, Guidance on sound insulation and noise reduction for buildings [7] were used to calculate the required performance dB Rw to be achieved by the building façade.

• This assessment concluded that the façade must achieve a minimum of 17dB Rw. This can be typically achieved using standard double glazing and a standard façade construction. High performance acoustic glazing and trickle ventilators are not required.

6 REFERENCES

[1] Guidance Note for Noise: License Applications, Surveys and Assessments in Relation to Scheduled Activities (NG4) ENVIRONMENTAL PROTECTION AGENCY: 2016

[2] Environmental Noise Guidelines for the European Region

WORLD HEALTH ORGANISATION: 2018

[3] ISO 1996-1:2016 Acoustics -- Description, measurement and assessment of environmental noise -- Part 1: Basic quantities and assessment procedures INTERNATIONAL STANDARDS ORGANISATION: 2016

[4] ISO 9613-2 Acoustics – Attenuation of sound during Propagation Outdoors – Part 2:

General Method of Calculation INTERNATIONAL STANDARDS ORGANISATION: 1996

[5] BS EN 1793-2 Road Traffic Noise Reducing Devices – Test method for determining the acoustic performance: Part 2 – Intrinsic characteristics of airborne sound insulation under diffuse sound field conditions. BRITISH STANDARDS: 2012

[6] BS EN ISO 10140-1:2010 Acoustics -- Laboratory measurement of sound insulation of building elements -- Part 1: Application rules for specific products INTERNATIONAL STANDARDS ORGANISATION: 2010

[7] BRITISH STANDARDS INSTITUTION, BS8233: 2014, Guidance on sound insulation and noise reduction for buildings (2014)

[8] DEPARTMENT FOR EDUCATION (UK), Building bulletin 93: Acoustic Design of Schools:

Performance Standards (February 2015)


Appendix A

Noise Monitoring Data

Location Period Measurement Start Time Elapsed Time LAeq LAF90.0 LAF10.0 LAFmax

N2 Day Meas001 22/05/2018 17:14 00:30:00 46.51 38.32 44.18 72.83

N2 Night Meas004 22/05/2018 23:40 00:30:00 39 37.77 40.07 55.01

N3 Day Meas002 22/05/2018 18:01 00:30:00 42.55 39.16 44.84 57.02

N3 Night Meas003 22/05/2018 23:02 00:30:00 40.7 36.66 43.29 52.37

N1 Day 62 22/05/2018 13:00 00:30:00 49.9 39.9 53.4 62.8

N1 Day 63 22/05/2018 13:30 00:30:00 49.2 39.2 52.9 59.5

N1 Day 64 22/05/2018 14:00 00:30:00 49.7 39.3 53.4 67.7

N1 Day 65 22/05/2018 14:30 00:30:00 50 39.2 53.9 61.4

N1 Day 66 22/05/2018 15:00 00:30:00 49.8 39.1 53.4 64.3

N1 Day 67 22/05/2018 15:30 00:30:00 49.7 39.8 53.3 64.3

N1 Day 68 22/05/2018 16:00 00:30:00 51 40.7 54.4 60.8

N1 Day 69 22/05/2018 16:30 00:30:00 51.5 42.4 54.6 73.8

N1 Day 70 22/05/2018 17:00 00:30:00 50.7 43.4 53.9 58.4

N1 Day 71 22/05/2018 18:00 00:30:00 51.8 42.4 55 63.7

N1 Day 72 22/05/2018 18:30 00:30:00 52.5 41.7 55.1 84.5

N1 Night 81 22/05/2018 23:00 00:30:00 48.2 38.2 52.6 62.3

N1 Night 82 22/05/2018 23:30 00:30:00 45 37.5 49.5 57.4

N1 Night 83 23/05/2018 00:00 00:30:00 45.2 36.4 49.1 59.2

N1 Night 84 23/05/2018 00:30 00:30:00 43 33 46.5 57.6

N1 Night 85 23/05/2018 01:00 00:30:00 43.5 31.6 47.2 59.1

N1 Night 86 23/05/2018 01:30 00:30:00 42.2 31.7 43.7 62.3

N1 Night 87 23/05/2018 02:00 00:30:00 41.9 32.1 43.5 61.4

N1 Night 88 23/05/2018 02:30 00:30:00 39.5 31.4 39.2 57.2

N1 Night 89 23/05/2018 03:00 00:30:00 41.5 32.6 42.1 59

N1 Night 90 23/05/2018 03:30 00:30:00 42 32.9 43.2 59.4

N1 Night 91 23/05/2018 04:00 00:30:00 48.6 35.7 48.7 70.3

N1 Night 92 23/05/2018 04:30 00:30:00 47.3 39.3 48.7 76.8

N1 Night 93 23/05/2018 05:00 00:30:00 46.8 39.4 49.5 64.4

N1 Night 94 23/05/2018 05:30 00:30:00 47.7 41.4 51.3 63.1

N1 Night 95 23/05/2018 06:00 00:30:00 49 41.8 52.8 63.2

N1 Night 96 23/05/2018 06:30 00:30:00 51.5 43.7 55.7 62

N1 Day 97 23/05/2018 07:00 00:30:00 52 45.4 55.5 63.8

N1 Day 98 23/05/2018 07:30 00:30:00 52.1 43.8 55.3 65

N1 Day 99 23/05/2018 08:00 00:30:00 51.6 41.3 54.6 66.1

N1 Day 100 23/05/2018 08:30 00:30:00 51.6 41.2 54.5 73.1

N1 Day 101 23/05/2018 09:00 00:30:00 51 40.5 54.1 67.1

N1 Day 102 23/05/2018 09:30 00:30:00 50.4 39 53.9 68.2

N1 Day 103 23/05/2018 10:00 00:30:00 50.4 39.2 53.9 61.9

N1 Day 104 23/05/2018 10:30 00:30:00 50.4 39.6 53.9 63.8

N1 Day 105 23/05/2018 11:00 00:30:00 50.2 39.5 53.8 62.9

N1 Day 106 23/05/2018 11:30 00:30:00 50.3 40.5 53.9 62.5

N1 Day 107 23/05/2018 12:00 00:30:00 50 39.7 53.6 60.1

N1 Day 108 23/05/2018 12:30 00:30:00 49.8 39.4 53.6 59.9

50.77 41.09 54.14 72.15

46.40 38.03 49.65 66.81

Sound Field Correction:

Bandwidth:

Time Weighting:

N1 - Average Day

N1 - Average Night

Allegro Acoustics

Irene Sofia Rodriquez BEng MEng MIEI

B&K Type 2250 and Cirrus Type CR:171B

2722891 and G066787

07/03/2018N and 08/05/2018

Free Field

1/3rd

Octave - Fully Integrating

Fast

Measurement Data

Testing Agency:

Testing Operator:

SLM:

SLM Serial Number:

SLM Factory Calibration Date:


Appendix B

Calibration Certification

Test Date: 06/03/2018

Type 4231

2725165

Description Serial Number

Signed on behalf of Sonitus Systems:

Allegro Acoustics Ltd

2 Riverside

Oldbawn

Calibration Standards

GRAS 42AA Pistonphone

Equipment Information

227947

228216

Certificate of Calibration

Issued to: Certificate Number

AC180324

Tallaght

GRAS 46A0 Pressure Field Microphone

The above calibrator was verified in line with the requirements of BS EN 60942:2003. The calibrator was

allowed to stablize for a suitable period, as described in the manufacturer's instruction manual, in laboratory

conditions. The sound pressure level in the cavity (half-inch). The operating frequency and signal distortion

were also measured.

Model:

Serial Number:

Calibration Procedure

Co. Dublin

Item Calibrated:

Make:

Acoustic Calibrator

Bruel & Kjaer

The standards used in this calibration are traceable to NIST and/or other National Measurement Institutes

(NMI’s) that are signatories of the International Committee of Weights and Measures (CIPM) mutual

recognition agreement (MRA).

National Instruments PXI-4461 19C91D2

Unit 1A, Trinity Technology and Enterprise Campus, Pearse Street, Dublin, D02 X940

www.sonitussystems.com Email: [email protected]

Type 4231

2725165

Measurement conditions were within the tolerances defined in BS EN 60942.

Barometric Pressure: 1040 hPa

Temperature: 20.3 °C

32 %

0.75 0.14 dB

20 Hz 0.25 Hz

4.0 0.3

RESULT: PASS

Notes

1. All measurements were made with the half-inch configuration of the calibrator in place.

2. The measurement uncertainty is reported as a standard uncertainty multiplied by a coverage factor k=2

which, for a normal probability distribution, corresponds to a coverage probability of approximately 95%.

3. The given uncertainty corresponds to measured values only and does not relate to the long term stability

of the device under test.

As public evidence was available, from a testing organization responsible for approving the results of pattern

evaluation tests, to demonstrate that the model of sound calibrator fully conformed to the requirements for

pattern evaluation described in Annex A of IEC 60942:2003, the sound calibrator tested is considered to

conform to all the Class 1 requirements of IEC 60942:2003

The manufacturer's guidelines concerning free-field correction should be observed when using the calibrator.

Calibration Report

Model:

Serial Number:

Equipment Information

Ambient Conditions

Results

Relative Humidity:

94 dB, 1KHz

Uncertainty

+/-

Sound pressure level (dB) 94.25

Frequency (Hz) 999.99

Distortion (%) 0.35

Calibrator

Setting

Measured

Parameter

Measured

Value

Tolerance

+/-

Unit 1A, Trinity Technology and Enterprise Campus, Pearse Street, Dublin, D02 X940

www.sonitussystems.com Email: [email protected]


Appendix C

Noise Level Calculations

No

ise

so

urc

eL w

A [

dB

]Lo

cati

on

Dis

tan

ce t

o N

SL,

r [

m]

L Ae

q [

dB

]N

um

be

r o

f it

em

sL A

eq

,to

tal [

dB

]In

sert

ion

Lo

ss [

dB

]A

tte

nu

ate

d

L wA [

dB

]

Att

en

ua

ted

L Ae

q [

dB

]

Att

en

ua

ted

L Ae

q,t

ota

l [d

B]

Pla

nt

eq

uip

me

nt

60

.58

N1

12

01

1.0

06

02

8.7

80

60

.58

11

.00

28

.78

60

.58

N2

18

07

.47

60

25

.26

06

0.5

87

.47

25

.26

87

.74

N1

12

03

8.1

61

38

.16

58

2.7

43

3.1

63

3.1

6

87

.74

N2

18

03

4.6

31

34

.63

58

2.7

42

9.6

32

9.6

3

59

.35

N1

12

09

.77

21

2.7

80

59

.35

9.7

71

2.7

8

59

.35

N2

18

06

.24

29

.25

05

9.3

56

.24

9.2

5

56

.76

N1

12

07

.18

21

0.1

90

56

.76

7.1

81

0.1

9

56

.76

N2

18

03

.65

26

.66

05

6.7

63

.65

6.6

6

To

tal

(Pla

nt

eq

uip

me

nt)

@ N

13

8.6

53

4.5

5

To

tal

(Pla

nt

eq

uip

me

nt)

@ N

23

5.1

33

1.0

3

65

N1

12

01

5.4

23

03

0.1

90

65

15

.42

30

.19

59

N2

18

05

.89

30

20

.67

05

95

.89

20

.67

To

tal

(Pla

nt

eq

uip

me

nt

+ S

tud

en

ts)

@ N

13

9.2

33

5.9

1

To

tal

(Pla

nt

eq

uip

me

nt

+ S

tud

en

ts)

@ N

23

5.2

83

1.4

1

So

un

d P

ress

ure

Le

ve

ls

Pe

op

le s

pe

ak

ing

no

rma

l

Stu

de

nts

Sta

nd

ard

Ba

thro

om

Fa

n

He

at

Pu

mp

(N

ZE

B)

AC

Un

it H

ea

tin

g

AC

Un

it C

oo

lin

g

nuig student accommodation, phase 2 · 2019-02-28 · report author: irene sofia rodriquez beng...

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