Sound Insulation Testing – Commercial

Approved Document E of the Building Regulations requires party walls and floors between ‘rooms for residential purposes’ (e.g. hotels, care homes, student accommodation) to demonstrate a basic level of sound insulation. 


There are 2 types of sound insulation test:

  • Airborne sound test – based on using a loudspeaker to generate around 100dB of pink noise in the ‘source’ room and measuring the sound pressure levels in a ‘receive’ room on the other side of a party wall or floor using a sound level meter. The difference in the levels is the basis for the sound insulation in decibels
  • Impact sound test – based on using a tapping machine to replicate footfall on to a floor in the ‘source’ room and measuring the sound pressure levels below in the ‘receive’ room, this includes structure-borne sound transmission.



For every 10 units, 1 set of tests must be conducted.

For rooms for residential purposes a set includes 1 airborne test on a party wall, 1 airborne test on a party floor and 1 impact test on a party floor.

The performance requirements are set at a level that should prohibit sounds at a ‘reasonable’ level being heard in a neighbouring room i.e. you shouldn’t be able to hear conversations and TVs at a normal volume but if someone is having a party or a very loud argument this will still be audible.

Alternatively, building contractors can demonstrate compliance by paying a licence fee for robust construction details and then a further fee for each time a wall is built using these design details or by conducting pre-completion acoustic testing of a sample of walls and/or floors on site.

For more information on sound insulation and the testing, please visit our FAQ page.




Our Sound Testing Process

Our air test engineers are home-based and well-placed to cover Greater London and the City, Kent, Essex, Surrey, Sussex, Hampshire, Berkshire, Buckinghamshire, Oxfordshire, Hertfordshire, Bedfordshire and Cambridgeshire, we are able to test all over the UK.

Our process is as follows:

1. Answer Queries

We are happy to talk through what is involved, what to watch out for, and when to test. We can provide guidance and checklists.


2. Date & Price

We provide a quote based on the number of units and sampling prescribed by Approved Document E – it is usually helpful to have PDF Plans to confirm the layout of party walls and/or floors relative to habitable spaces.

3. Preparation

We confirm a date. Our engineer will call you ahead of the test date to talk you through the preparation and process plus agree the timings.

4. On the day of testing

Airborne tests involve creating noise of a known level (approximately 100dB) on one side of the party/separating wall/floor and measuring the volume on the other side to calculate the amount of noise that the wall or floor is insulating. Measurements are taken in multiple planes and positions, reverberation (echo) and background noise are taken into account. The result is expressed in decibels (dB) as DnTw with corrections including traffic noise (Ctr).

Impact testing is done using a tapping machine that simulates footfall on the uncovered floor surface. The level of noise is measured in the unit below and the result is expressed in dB as LnT.

New flats and houses must achieve greater than or equal to 45dB sound insulation for airborne tests and less than or equal to 62dB for impact tests. Converted properties have slightly easier targets.

Testing typically takes place very close to completion but before carpets or other flooring is laid.

Please see FAQs.

5. Paperwork

We issue a short-form UKAS test report including certificates for each test.

If the worst should happen and there is a failure, we put you in touch with an experienced acoustician who can provide design/remedial advice ahead of retesting.

Established in 2002


What our clients say about us

“ALT were extremely helpful and knowledgeable. They worked with the site team to identify and resolve issues during construction.”
“I have used Air Leakage Testing Ltd on two separate occasions at my property and found them to be extremely thorough and professional at all times. The turnaround between site visit and subsequent reports was quick and efficient - making my life a whole lot easier! Would highly recommend to anyone!”


Helpful Engineers

We work with you to achieve the best result, identifying potential issues and repeating the testing once these have been addressed. We are on hand to answer any questions before, during and after the testing.

Flexible & Responsive

We try to fit in with the dates and times you need the test, we try to work around other trades to minimise disruption on site. We issue quotes and certificates within 1 working day, our lead-times are typically around a week but we will try and fit you in sooner if required.


We have been air testing since 2002 and all our test engineers have a vast amount of experience.

Great value

Our prices are very competitive but we can also undertake air and sound testing on the same visit to save you more money. If you do manage to find the testing cheaper, we will beat any quote.

Get a quote

Fill in the form at the top of this page, and we will provide an estimated cost.

Provide more information, and we will issue a formal quotation.