Technical Booklet G Resistance to the Passage of Sound·Page 45·2.73
Minimum mass requirement for masonry inner leaf
The masonry inner leaf of the external cavity wall must have a mass per unit area of at least 120 kg/m² excluding finish, except where separating wall types 2.1, 2.3 or 2.4 are used.
The masonry inner leaf should have a mass per unit area of at least 120 kg/m2 excluding finish. However, there is no minimum mass requirement where separating wall type 2.1, 2.3 or 2.4 is used.
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