Technical Booklet G Resistance to the Passage of Sound·Page 37·2.46, 2.47
Junctions with internal concrete floors
Internal concrete floor slabs may only pass through a type 1 separating wall if they have a mass per unit area of at least 365 kg/m². Hollow-core planks and composite beam floors must not be continuous through the wall.
An internal concrete floor slab may only be carried through a type 1 separating wall if the floor base has a mass per unit area of at least 365 kg/m² (see Diagram 2.11). Internal hollow-core concrete plank floors and concrete beams with infilling block floors should not be continuous through a type 1 separating wall.
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