Technical Booklet G Resistance to the Passage of Sound·Page 55·2.115
Junctions with internal timber floors - floor joists on separating wall
Floor joists supported on a separating wall must be hung on hangers rather than built into the wall to maintain acoustic performance.
If the floor joists are to be supported on the separating wall then they should be supported on hangers and should not be built in (see Diagram 2.33).
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