Technical Booklet G Resistance to the Passage of Sound·Page 95·4.27
Independent ceiling support methods
The ceiling must be supported either by independent joists fixed only to surrounding walls with at least 25 mm clearance above existing floor, or by independent joists with additional resilient hangers attached to the existing floor base.
The ceiling should be supported by one of the following methods –
(a) independent joists fixed only to the surrounding walls. A clearance of at least 25 mm should be left between the top of the independent ceiling joists and the underside of the existing floor construction; or
(b) independent joists fixed to the surrounding walls with additional support provided by resilient hangers attached directly to the existing floor base.
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