Colorcoat-Online - Acoustic Performance

Acoustic Performance

Noise and its control are important aspects of building design. Whilst Building Regulations in this area focus on the transmission of noise between separating wall and floor constructions and not the external shell, the building envelope can play a key role in keeping internal noise in or external noise out. Here a brief outline of the basic terminology of acoustics is provided as well as an overview of Building Regulations and a focus on the acoustic parameters of a building. This is supported by practical guidance on acoustically enhancing pre-finished steel cladding systems where required.

Definition of Sound

Sound is the sensation felt by the human ear due to rapid pressure fluctuations in the air. There are two important parameters which govern a sound. One is its magnitude and the other is the frequency.

Acoustic Regulations

Current UK Building Regulations require acoustically robust building standards to improve soundproofing in new homes and schools. In other words, the government has made it law that noise is dealt with adequately in the buildings we create. The acoustic Building Regulations apply to new build or conversions of buildings which are to be used as dwellings or residential accommodation where people either live or sleep

Acoustic performance parameters in buildings

When a sound hits a wall or a partition it goes three ways. Some of the sound will be reflected, some will be absorbed and converted into heat, and some will be transmitted into the room of a building. The fractional reduction of incident sound which is transmitted is defined as the Sound Reduction Index (SRI) or equally known as the transmission loss. This transmission loss for a particular construction is measured in a laboratory based on the methodology provided by BS EN ISO 140-3: 1995.

Acoustic strategies

The acoustic response of a cladding system will depend on its mechanical properties. A good rule of thumb is that the stiffer the panel, the more sound it will transmit. A profiled steel sheet of a given thickness can produce the same structural strength as a flat panel of substantially greater weight and thickness.