Technical Booklet G Resistance to the Passage of Sound·Page 71·3.36
Junctions with external cavity walls with timber frame inner leaf
External cavity walls with timber frame inner leaf must have the cavity closed with a cavity stop and the inner leaf finished with two layers of plasterboard (minimum 10 kg/m² each) with sealed joints.
Where the external wall is a cavity wall –
(a) the outer leaf of the wall may be of any construction;
(b) the cavity should be closed with a cavity stop; and
(c) the wall finish of the inner leaf of the external wall should be two layers of plasterboard, each sheet of plasterboard to be of minimum mass per unit area 10 kg/m2, and all joints should be sealed with tape or caulked with sealant.
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