What is a sound test?

Under TGD E of the current building regulations a sample of testing is required for all new residential developments to show the party walls and floors achieve a minimum sound resistance. The regulations require airborne sound test through party walls and floors. Impact test are also required between party floors. These regulations were introduced in 2014

An airborne sound test is carried out by creating a loud noise using a large speaker on one side of the wall and recording how much of that noise comes through the wall using a sound level meter. The same method applies to testing through floors. In order to carry out a sound test, the tester will need access to the two dwellings being tested and the dwellings need to be unoccupied

If the sound test fails to achieve the minimum rating, there may be an obvious cause such as vents too close together or holes in the party walls/floors. A failure will be the result of insufficient density in the wall/floor, or inconsistency in the building fabric. However noise transfer can be very complicated and a design solution will usually be required by an acoustic engineer. The engineer will design a solution based on the results from the sound test.