Technical Booklet G Resistance to the Passage of Sound·Page 45·2.75
External cavity wall with timber frame inner leaf
Where the external wall is a cavity wall with a timber frame inner leaf, the outer leaf may be of any construction and the cavity must be closed with a cavity stop.
Where the external wall is a cavity wall –
(a) the outer leaf of the wall may be of any construction; and
(b) the cavity should be closed with a cavity stop (see Diagram 2.22).
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