Building Regulations and Testing

Our acoustic systems have been designed to comply with, and exceed, the latest Building Regulations across the UK. They are suitable for Pre-Completion Testing and systems are available that comply with Robust Details FFT1, FFT2, FFT3 & FFT4. We also provide an on site pre-PCT testing service by independent acousticians to find the most appropriate acoustic solution for each situation.

Pre-completion Testing

Part E states that 10% of all units constructed on site must be pre-completion sound tested (PCT) on site. The separating walls and floors within each unit must be tested to show compliance. A test body with appropriate third party accreditation (ANC, UKAS) to ensure that the required acoustic ratings have been achieved must carry out relevant tests. These tests must then be submitted to Building Control who will check to make sure that the performance requirements have been met.

The separating walls between flats and the communal areas do not require a sound test. These walls must however comply with the sound insulation requirements within Document E. The developer / contractor will need to make sure that the wall construction between these areas has an adequate performance to achieve the required standards.

PCT can be used on all types of building, both new build and refurbishment / materials change of use, which contain rooms for residential purposes.

There is a standard acoustic test that is carried out on residential properties which measures the performance of both airborne and impact sound levels. There are two parts to the test:

Airborne

The loudspeaker in the Source Room emits a loud noise, over a range of frequencies, which is known as pink noise.

The microphone in the Source and Receiving Room measures the sound pressure level. Using specialist equipment, the acoustician can then calculate the airborne sound insulation (DnT,w + Ctr).

What is being measured is the difference in sound level between the Source Room and the Receiving Room, so the greater the value the better the acoustic performance.

Impact

In the Source Room a tapping machine impacts repeatedly directly onto the floor structure.

A microphone in the Receiving Room measures the sound pressure level and the recorded level produces the Impact result (L’nT,w). The lower this figure is, the better the acoustic performance.

Approved Document E

On 1st July 2003, the new Approved Document E of the Building Regulations came into force in England and Wales. It is designed to meet demands for improved acoustic insulation and combat the problems of noise pollution from neighbours.

These new regulations, unlike previous requirements, apply to both new build and refurbishment or conversion projects on all types of dwellings including, flats and apartments, semi detached and terraced housing, hotels, hostels, nursing homes and student accommodation. It applies to the separating walls, floors and ceilings between different dwellings only and not to those within the same dwelling.

One of the main differences of the new regulations is how airborne performance is now measured. A spectrum adaptation term (Ctr) is now applied, which puts a much greater emphasis on low frequency sound (100Hz to 315Hz). These low frequencies are the cause of much modern noise pollution but are also among the most difficult to combat.

Approved Document E can be downloaded from www.planningportal.gov.uk or www.communities.gov.uk.

Sound tests

Sound Test data is frequently used to show how a specific acoustic solution will perform. However, caution is required when using this data because it can be presented in two different forms.

Laboratory sounds tests are often used to show performance but these tests are not as reliable as field sound tests conducted onsite. This is because a laboratory sound test only tests the system in a perfect environment, where no flanking sound exists. Consequently, acousticians only use laboratory sound test as an indicator of performance and would not generally expect products to perform to that standard onsite.

A field sound test provides a true reflection of performance, because there will be some degree of flanking sound onsite and gives the realistic performance that can be expected from the system being tested. Therefore, when specifying a specific acoustic solution, always check Field Test data and not just Laboratory tests.