Technical Booklet G Resistance to the Passage of Sound·Page 35·2.39
Masonry inner leaf mass requirement where separating floor present
When a separating floor is also present, the minimum mass per unit area requirement of 120 kg/m² for the masonry inner leaf always applies, regardless of any openings in the external wall.
Where there is also a separating floor then the requirement for a minimum mass per unit area of 120 kg/m2 excluding finish should always apply, irrespective of the presence or absence of openings.
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