Technical Booklet G Resistance to the Passage of Sound·Page 79·3.70
Masonry inner leaf mass requirement for external cavity walls
The masonry inner leaf of an external cavity wall must have a minimum mass per unit area of at least 120 kg/m2 excluding finish.
The masonry inner leaf of an external wall cavity wall should have a mass per unit area of at least 120 kg/m2 excluding finish.
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