Technical Booklet G Resistance to the Passage of Sound·Page 36·2.41
External cavity wall with timber frame inner leaf - construction requirements
The framed inner leaf must abut the separating wall with vertical ties at maximum 300 mm centres, and the wall finish must be one or two layers of plasterboard with minimum 10 kg/m² mass per unit area, with all joints sealed or caulked.
Where the inner leaf of an external cavity wall is of framed construction, the framed inner leaf should –
(a) abut the separating wall; and
(b) be tied to it with ties at not more than 300 mm centres vertically.
The wall finish of the framed inner leaf of the external wall should be –
(c) one layer of plasterboard; or
(d) two layers of plasterboard with staggered joints where there is a separating floor; and
(e) each sheet of plasterboard to be of minimum mass per unit area 10 kg/m²; and
(f) all joints should be sealed with tape or caulked with sealant.
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