Technical Booklet G Resistance to the Passage of Sound·Page 71·3.41
Junctions with floor penetrations (excluding gas pipes)
Pipes and ducts penetrating separating floors between flats must be fully enclosed within each unit with holes sealed with tape or sealant.
Pipes and ducts that create a hole that penetrates a floor separating habitable rooms in different flats and maisonettes should be enclosed for the full height in each flat and maisonette (see Diagram 3.6).
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