Technical Booklet G Resistance to the Passage of Sound·Page 86·3.103
Cavity wall with masonry inner leaf - outer leaf and cavity
Defines requirements for the outer leaf and cavity closure of external cavity walls with masonry inner leaves in sound-resistant floor junctions.
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 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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