Sound Insulation

Two parameters are used to describe the sound insulation of a partition, Dw and Rw. Dw represents the sound insulation between rooms on-site. Since these figures describe the fnal site requirements, Dw levels are specified by clients and Building Regulations. Rw represents the lab tested sound insulation of an element making up a partition wall/floor type. Due to flanking and other factors, lab rated sound reduction levels will not be achieved on-site. Conventionally, there is a 5 to 10 dB reduction between a Rw lab tested figure and an on-site Dw figure. The conversion between Dw and Rw is relatively complex and takes into consideration receiver room volume, receiver room reverberation times and the area of the separating partition. The conversion between Rw and Dw should always be calculated.

How loud is too loud?

Continued exposure to noise above 85 dBA (adjusted decibels) over time will cause hearing loss. The volume (dBA) and the length of exposure to the sound will tell you how harmful the noise is.

In general, the louder the noise, the less time required before hearing loss will occur.

Noise Disturbance

Building acoustics can help to mitigate the effects of noise disturbance which can have negative effects on health, well-being and general quality of life.

The Noise Policy Statement for England (NPSE) defines noise pollution as:

- Environmental noise: which includes noise from transportation sources. - Neighbour noise: which includes noise from inside and outside buildings. - Neighbourhood noise: which includes noise arising from industrial and entertainment premises, trade and businesses, construction sites and noise in the street.

This can be an important consideration for the location, design and construction of new developments.