home » performance characteristics: sound reduction »

Noise can be a major nuisance and achieving reasonable levels of acoustic control with sound reduction between different parts of a building or between outside and inside, may be essential to the usability and viability of historic properties. Original doors and frames are largely ineffective, particularly if they are in poor condition, as any gaps allowing leakage of air will substantially reduce sound reduction. Statutory control of sound reduction is currently limited, with Part E of the Building Regulations covering converted (as well as new-build) housing and other residential uses. Here, doors between communal corridors and rooms in flats should have good perimeter seals and achieve at least a sound reduction index of 29RwdB or have a minimum mass per unit area of 25kg/m2. While there is some guidance on doors within a dwelling, no specific values are applied in the Regulations – as is the case for entrance doors to the outside. It could be argued that more needs to be done in a world of increasing housing densities and growing external noise.

Longden doorsets can achieve a sound reduction value of 30RwdB incorporating acoustic seals, while up to 38RwdB is available with more specialised panelled door constructions whilst maintaining the original aesthetic appearances. Please refer to the table on fire resistance.

The tested values shown in the table on page 38 relate to single leaf doors. Double leaf pairs are available, however a slight reduction in performance can be expected from the single leaf value.

The following provides general guidance on acoustic privacy in relation to sound reduction:

25RwdB Normal speech easily overheard 30RwdB Loud speech clearly overheard 35RwdB Loud speech can be distinguished 40RwdB Loud speech heard but not intelligible 45RwdB Loud speech heard faintly 50RwdB Loud and shouting speech can be heard with difficulty