A sound insulation test is a measure of how much sound gets transmitted from one room to another, for rooms which are either next to each other (party wall sound insulation) or one above the other (sound insulation between floors).
As a responsible developer you want to make sure that the sound insulation between dwellings is of a good enough standard to stop future occupants disturbing each other. It is also covered by Building Regulations Approved Document E which requires testing to be carried out to demonstrate ‘reasonable resistance to sound from other parts of the same building and from adjoining buildings’. This is defined by a noise index specified in British Standard BS EN ISO 717.
The person carrying out the building work should arrange for sound insulation testing to be carried out by a test body with appropriate third-party accreditation in accordance with Approved Document E states that. This includes members, of the Association of Noise Consultants Registration Scheme.
In simple terms, the test involves making a noise in one room and measuring how much noise/sound can be measured in the room next door, or above and below. A measurement of impact sound transmission is also made by using a ‘tapping machine’ on the floor and measuring the level in the room below.
In practice, the tests are carried out using specialist equipment and a methodology specified in British Standard BS EN ISO 140, which requires measurements at a number of locations and a test of ‘reverberation time’ in the receiving room.