Refurbishment and Fit Out / International / 2015 / 09 - Pollution /
POL 05 - Noise Attenuation
Information correct as of 2ndDecember 2024. Please see kb.breeam.com for the latest compliance information.
Achieving a reduction in noise levels where background levels are low - KBCN1692
Where existing background levels are low, such as during night-time, there is no dispensation or flexibility that can be applied in achieving the requirements. The aim of the issue is to reduce the potential impact of noise from the assessed building to local noise-sensitive buildings. Acoustic experts have confirmed that the requirements for the background noise levels are still appropriate where existing levels are low, including where a 5dB reduction is stated within the criteria.
Campus with multiple building assessments - KBCN0597
If a campus development project has multiple building assessments being built in conjunction with each other, each building should be assessed independently. Where there are noise sensitive buildings; including any new buildings in the process of being built, the criteria requirements must still be met.
Compliant attenuated noise levels - KBCN00047
BS 4142 noise level requirements can be used to demonstrate compliance provided the best practice testing methodologies for noise attenuation outlined in BS 7445 are followed.
Existing plant – Noise impact assessment - KBCN0640
The existing background noise level should not include existing plant associated with the assessed building (criterion 2.a.i). Both existing and newly specified externally mounted plant should be considered within the noise impact assessment as part of the ‘rating noise level’ (criterion 2.a.ii).
However, for Part 2 only and Part 3 only assessments, as indicated in the relevant CNs within the manual, only the noise impact of existing or new externally mounted plant specified within the scope of that Part is to be considered.
For example, in a Part 3 only assessment, where existing plant forms part of the core services and new plant is installed as part of the local services, only the impact of the noise generated by the new plant should be considered. The existing plant noise should be included as part of the existing background levels.
Issue Pol 05 assesses the impact of existing and newly specified externally mounted plant and the impact of any fabric measures on reducing the impact of noise on any nearby noise-sensitive buildings. Its applicability is relevant to all treated buildings where Part 1 is included, even where the existing plant is not being upgraded and is scope dependent when Part 2 or Part 3 only assessments are carried out.
13.08.18 KBCN content amended to include consideration of Part 2 or Part 3 only assessments.
This will be clarified in the next manual re-issue.
03.11.2021 Issue 2.0 of the UK RFO technical manual amended.
International suitably qualified professionals - KBCN1266
In some issues the International NC and RFO schemes prescribe specific requirements for suitably qualified professionals. We appreciate that some countries might have different recognition schemes in place, and these might differ from the BREEAM requirements. Where this is the case, assessors should submit a technical query with appropriate information, and we will review and approve each situation on a country basis.
No external plant specified - KBCN0931
Where there is no external plant specified and the acoustician confirms that there is no significant noise source, it is acceptable for the acoustician to provide a formal statement in lieu of the noise impact assessment. All other evidence for this issue must be provided as listed in the Evidence table.
The formal statement should be produced by a 'suitably qualified acoustician' (as defined in the Relevant Definitions for this issue) and should justify this approach with reference to the specific internal plant to be installed and the proximity of any noise sensitive areas or buildings.
The statement must explain clearly how the aim of the issue is being met.
Post construction noise level testing - KBCN00043
Noise level measurements do not need to be taken at the post construction stage if the acoustician has accurately modelled the noise level from the plant, using manufacturer's literature, and site measurements taken at the design stage. Any attenuation measures specified by the acoustician in their report must be confirmed as being present post construction.
If the acoustician has been unable to model the noise level accurately, post construction measurements are needed to demonstrate compliance.
Calculations and recommendations from the acoustician are relied on to be accurate and in keeping with best practice; attenuation measures are assumed to be specified and installed correctly.
Scope of issue – clarification – fixed installations - KBCN1660
The scope of this issue covers noise from external building services (or 'fixed installations' as written in the manual) serving areas
designed for human comfort.
The noise impact assessment excludes:
- Noise from process-related plant.
- Noise from emergency or back-up plant which are not used during normal operation.
Temporary power solutions in noise impact assessments - KBCN0171
Plants such as standby generators that are only used temporarily are excluded from the noise impact assessment.
Verification of measurements undertaken by non-SQA - KBCN1661
It is acceptable for individuals who do not meet the BREEAM definition of a suitably qualified acoustician (SQA) for Pol 05 to undertake the testing for this issue, provided the measurements or calculations are verified by a SQA. The SQA must review the report and confirm in writing that they have found it to:
- Represent sound industry practice
- Be appropriate given the building being assessed and scope of works proposed
- Avoid invalid, biased and exaggerated recommendations
Additionally, written confirmation from the SQA how they comply with the definition of a SQA is required.
Information correct as of 2ndDecember 2024. Please see kb.breeam.com for the latest compliance information.