Acoustic Assessment
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Report Fighting Cocks Bar & Venue 56 Old London Road, Kingston upon Thames Acoustic Assessment Prepared by J. R. Tee BSc. (Hons.) MIOA Date 23rd June 2015 Project No 1414725 Contents 1.0 Introduction 2.0 Assessment Methodology and Criteria 3.0 Noise Survey and Sources 4.0 Road Traffic Noise Assessment 5.0 Sound Insulation between Residential Element and the Commercial / Retail / Venue Element 6.0 Mechanical Services Plant Noise Assessment 7.0 Conclusions Appendices A. Acoustic Terminology B. Site Plan C. Noise Survey Results Document reference R1-23.6.15-Fighting Cocks Kingston Upon Thames-1414725-JRT Page 2 1.0 Introduction 1.1 Sharps Redmore has been instructed by Mr J. O’Grady, of the Fighting Cocks Bar and Venue, to undertake an environmental noise survey and acoustic assessment at his proposed site. The proposal is at 56 Old London Road, Kingston upon Thames and comprises the redevelop of the site by retaining an element of the public bar on the ground floor, constructing a new basement music venue, provide a separate ground floor commercial/retail unit, and eight self-contained residential flats from first to second floors. There will be an element of refurbishment and new build in this proposal. 1.2 The site overlooks Old London Road to the north and Fairfield North road, which forms part of the A308, to the south. There are existing retail units neighbouring the site and residential dwellings on the opposite sides of the roads. It is the purpose of this assessment to assess the impact of the road traffic noise to the proposed new residential accommodation. The new location of music venue will be considered in regards to noise disturbance to the proposed new residential accommodation above. Noise from any plant or air conditioning associated with these uses has the potential to disturb, so this has also been considered. 1.3 Measurements were undertaken of the environmental noise levels experienced at both sides of the site; these are detailed in Section 3.0. Sections 4.0, 5.0 and 6.0 consider the noise impact from road traffic, the music venue and mechanical servicing plant noise. Assessment conclusions are in Section 7.0. 1.4 Appendix A contains acoustic terminology used in this report and a guide to the use of statistical indices. 1.5 The following areas will be assessed: the glazing specification to achieve internal noise level criteria; the separating partitions to the ground floor commercial unit and the basement music venue; and external mechanical services plant noise. Document reference R1-23.6.15-Fighting Cocks Kingston Upon Thames-1414725-JRT Page 3 2.0 Assessment Methodology and Criteria 2.1 The National Planning Policy Framework (NPPF) sets out the Government’s economic, environmental and social planning policies for England and “these policies articulate the Government’s vision of sustainable development.” In respect of noise, Paragraph 123 of the NPPF states the following: Planning policies and decisions should aim to: avoid noise from giving rise to significant adverse impacts27 on health and quality of life as a result of new development mitigate and reduce to a minimum other adverse impacts27 on health and quality of life arising from noise from new development, including through the use of conditions, recognise that development will often create some noise and existing businesses wanting to develop in continuance of their business should not have unreasonable restriction put on them because of changes in nearby land uses since they were established;28 and identify and protect areas of tranquillity which have remained relatively undisturbed by noise and are prized for their recreational and amenity value for this reason 27 See Explanatory Note to the Noise Policy Statement for England (Department for the Environment, Food and Rural Affairs). 28 Subject to the provisions of the Environmental Protection Act 1990 and other relevant law. 2.2 The NPPF reinforces the March 2010 DEFRA publication, “Noise Policy Statement for England” (NPSE), which states three policy aims, as follows: “Through the effective management and control of environmental, neighbour and neighbourhood noise within the context of Government policy on sustainable development: avoid significant adverse impacts on health and quality of life; mitigate and minimise adverse impacts on health and quality of life; and where possible, contribute to the improvement of health and quality of life.” 2.3 Together, the first two aims require that no significant adverse impact should occur and that, where a noise level which falls between a level which represents the lowest observable adverse effect and a level which represents a significant observed adverse effect, then according to the explanatory notes in the statement: “… all reasonable steps should be taken to mitigate and minimise adverse effects on health and quality of life whilst also taking into consideration the guiding principles of sustainable development. This does not mean that such effects cannot occur.” Document reference R1-23.6.15-Fighting Cocks Kingston Upon Thames-1414725-JRT Page 4 2.4 It is possible to apply objective standards to the assessment of noise and the design of new dwellings should seek to achieve these objective standards. Such guideline values are given in the World Health Organisation document “Guidelines for Community Noise” and these are replicated within a British Standard, BS 8233:2014. 2.5 The WHO guideline values are appropriate to what are termed “critical health effects”. This means that the limits are at the lowest noise level that would result in any psychological, physiological or sociological effect. They are, as defined by NPSE, set at the Lowest Observed Adverse Effect Level (LOAEL), but do not define the level above which effects are significant (the SOAEL). Compliance with the LOAEL should, therefore, be seen as a robust aim. 2.6 The WHO LOAEL guideline values are summarised in table 1 below: Table 1: WHO LOAEL guideline values Value Guidance Location Few seriously annoyed, Daytime and Continuous noise, L = 55 dB AeqT evening. outdoor living areas Few moderately annoyed, Daytime Continuous noise, L = 50 dB AeqT and evening. outdoor living areas Acceptable level to avoid speech Continuous noise, L = 35 dB AeqT interference, daytime and evening. Dwellings, indoors Continuous noise, L = 30 dB To avoid sleep disturbance at night. AeqT Bedrooms, indoors Noise peaks, L = 45 dB To avoid sleep disturbance at night. AMAX Bedrooms, indoors 2.7 The national interpretation of the WHO guidelines is contained in BS 8233:2014 'Guidance on sound insulation and noise reduction for buildings'. BS 8233 recommends the following indoor ambient noise levels for dwellings: Table 2: BS 8233 indoor ambient noise levels for dwellings Activity Location 07:00 to 23:00 23:00 to 07:00 Resting Living Room 35 dB LAeq, 16Hr -- Dining Dining room/area 40 dB LAeq, 16Hr -- Sleeping (daytime Resting) Bedroom 35 dB LAeq, 16Hr 30 dB LAeq, 8Hr 2.8 Combining the two sets of guidance would give the following design targets for new dwellings, which would represent compliance with the robust LOAEL: Gardens LAeq,T = 50 - 55 dB Living rooms LAeq,T = 35 dB Bedrooms LAeq,T = 30 dB LAMAX = 45 dB Document reference R1-23.6.15-Fighting Cocks Kingston Upon Thames-1414725-JRT Page 5 2.9 This is considered a robust but balanced view in the context of current policy. If, for practical reasons, these internal noise limits are not achievable, some flexibility (up to 5 dB relaxation of LAeq criteria) may be available. This is stated in BS 8233:2014 “Where development is considered necessary or desirable, despite external noise levels above WHO guidelines, the external target levels may be relaxed by up to 5 dB and reasonable internal conditions still achieved”. 2.10 In order to ensure the proper control of fixed plant or equipment (including mechanical services) that may be operated at this site as a consequence of this development, the appropriate assessment methodology is to compare the noise levels resulting from such operation against the background noise level (LA90) of the area. This is the method employed by BS 4142:1997 to determine the likelihood of complaint from noise of an industrial nature. 2.11 BS 4142 enables the likelihood of complaint to be determined according to the following summary process: i. Determine the background noise levels, in terms of the index LA90, at the receptor locations of interest. ii. Determine the specific noise level of the source being assessed, in terms of its LAeqT level (T = 1 hour for day or 5 minutes for night), at the receptor location of interest. iii. Correct (penalise) the rating level, if the source noise is of tonal or intermittent nature so as to attract attention. The correction factor is 5 dB. The resultant level is termed the rating noise level. iv. Compare the rating noise level with the background noise level; the greater the difference between the two, the higher the likelihood of complaint of the noise. v. Differences (rating – background) of around +10 dB indicate that complaints are likely; a difference of +5 dB is of marginal significance; a difference of -10 dB is a positive indication that complaints are unlikely. vi. The general intent of the planning system is to ensure that a development does not result in “significant environmental impacts”. This is, in our judgement, equivalent to the BS 4142 marginal significance criterion of +5 dB. 2.12 The Royal Borough of Kingston upon Thames Council’s Adopted Core Strategy document does not contain specific levels in relation to mechanical services plant noise, but it does infer that noise pollution should be taken into account. The document highlights their desire for all developments to achieve BREEAM credits.