PPG24 or Planning Policy Guidance note 24 was written to guide local authorities on using their planning powers to minimize the impact of noise on a proposed development. PPG24 is published by the DCLG and is used by local authorities throughout England and Wales. The area of planning and noise is awash with often contradictory guidance, standards, codes of practice, and it is unusual that any one of these documents precisely covers all aspects of a case. PPG24 requires a noise survey to be conducted at the planning stage to assess the overall suitability of the site's noise climate for residential development. With it comes the possibility of noise control measures being necessary as part of the planning conditions.

The purpose of a PPG24 planning condition is to ensure that future occupiers/residents of the proposed development will be able to sleep at night and enjoy their living rooms and gardens by day. PPG24 makes reference to internal and external acceptable noise levels identified in World Health Organization guidelines on community noise and BS8233.

PPG24 Noise Surveys are environmental noise assessments which are usually required at the planning application stage of a residential development. The purpose of a PPG24 noise survey is to assess the noise levels on a proposed site to ensure occupiers will not be adversely affected by noise from sources such as roads, railways and aircraft so reducing the chance of complaints once the residents have moved into the development.

Who can undertake the noise assessment?

A PPG24 noise assessment is conducted by an acoustic consultant such as Air Pressure Testing to assess the noise levels from sources such as roads, rail and aircraft. When appointing your acoustic consultant it is worth checking that they are a UKAS accredited as the local authority usually insists on this as a minimum requirement.

Whats the duration of the noise assessment?

The PPG24 noise survey should identify both daytime (07:00-23:00) and night time (23:00-07.00). PPG24 noise survey should be carried out over a typical working day, i.e. not weekends or bank holidays as the noise environment for these periods are unlikely to be typical. Other factors to take into consideration are weather conditions; adverse temperature may have an effect on monitoring equipment or wet conditions which may increase noise levels and render the noise assessment unrepresentative.
For clarification the noise exposure categories, which the local planning authority would determine are:

NEC A. Noise need not be considered as a determining factor in granting planning. The noise level at the high end of the category should not be regarded as a desirable level.

NEC B. Noise should be taken into account when determining planning applications and, where appropriate, conditions imposed to ensure an adequate level of protection against noise.

NEC C. Planning permission should not normally be granted. Where it is considered that permission should be given, for example because there are no alternative quieter sites available, conditions should be imposed to ensure a commensurate level of protection against noise.

NEC D. Planning permission should normally be refused.

Once the noise levels are Internal noise levels within the proposed buildings can be calculated using our latest noise prediction software. For most buildings, the overall sound insulation performance of the building envelope will depend on the glazing system employed. It may be necessary to stipulate specific glazing and ventilation systems that must be employed to ensure that internal noise criteria are achieved. Most new residential development, once constructed, must have Sound Insulation testing undertaken in accordance with Approved Document E of the Building Regulations. This normally included airborne wall & floor testing as well as impact tests.

Simple design measures to control noise.

Layout, orientation and screening of buildings should be considered before sound insulation design:

Position and orientate the development to minimize noise disturbance, i.e. minimize windows on the elevation facing traffic.

Where possible avoid placing bedrooms next to kitchens, living rooms or bathrooms in adjacent properties.

Where possible avoid placing bedrooms next to stairwells, entrance halls or lift shafts.

Ideally no windows should face a busy road, railway or commercial activity. If this is not possible, only windows of non-habitable rooms such as kitchens and bathrooms should face a noise source.

We pride ourselves on being able to deal with the issues in a direct and simple manner. Problems relating to noise during the planning stages can usually be avoided or resolved with a good, detailed and accurate acoustic assessment report. As standard all our reports include highly sophisticated noise mapping to accurately detail the spread of noise in the surrounding area for any particular situation. Using the latest acoustic modeling software we can create the situation and then visually model the results of many various mitigation measures in line with the associated planning condition.

What instruments should is used.

APT Acoustics use the latest Norsonic class 1 integrating sound level meters, conforming to BS 6698/IEC 61672. The noise survey should not be undertaken with anything less than a class 1 Analyzer which has been UKAS calibrated.

How do I know the equipment is accurate?

The instrument shall be calibrated to the manufacturers standard or by a National Accreditation of Measurement and Sampling UKAS accredited laboratory within the last year. A current certificate of calibration should be available and a copy included in the assessment report. The response of the instrument should be carefully checked before and after each measurement using a field calibrator. The portable calibrator should itself have been calibrated by a UKAS accredited laboratory within the previous 12 months. A current certificate of calibration should be available and a copy included in the PPG24 noise assessment report.

We undertake accurate on-site noise assessments to suit the needs of a clients problem and their pocket, and deliver concise and clear reports in a timescale designed to suit the client and to satisfy the relevant planning condition.

If you require more information on noise assessments for planning then please contact us now at: [email protected] or phone us on: 01525 303905.