External masonry walls

6.1.5Acoustic resistance

External walls adjacent to separating walls shall be designed to resist flanking sound transmission.

Acceptable levels of sound reduction between homes may be achieved by:

  • the inner leaf of an external cavity wall having sufficient density
  • sealing air paths
  • allowing appropriate spacing between the openings in external walls.

The density of external walls and the position of openings adjacent to separating walls should be in accordance with Building Regulations and, where relevant, an assessment which complies with Technical Requirement R3.