Technical Booklet G Resistance to the Passage of Sound·Page 83·3.90
Junctions with separating wall type 3.3 - Leaf mass requirement
Any leaf supporting or adjoining the floor must have a mass per unit area of at least 120 kg/m² excluding finish.
The mass per unit area of any leaf that is supporting or adjoining the floor should be at least 120 kg/m2 excluding finish.
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