Technical Booklet G Resistance to the Passage of Sound·Page 44·2.71
Junction requirements for external cavity walls with masonry inner leaf
Specifies construction requirements for junctions with external cavity walls, including options for cavity closure and acceptable fill materials to control sound transmission.
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 (for wall types 2.1 and 2.2 see Diagram 2.19, for wall types 2.3 and 2.4 see Diagram 2.20) unless the cavity is fully filled with mineral wool or expanded polystyrene beads (seek manufacturer's advice for other suitable materials).
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