Technical Booklet G Resistance to the Passage of Sound·Page 39·2.56
Sealing lightweight aggregate blocks above ceiling level
Lightweight aggregate blocks with density less than 1200 kg/m³ used above ceiling level must have one side sealed with cement paint or plaster skim to improve sound resistance.
If lightweight aggregate blocks of density less than 1200 kg/m3 are used above ceiling level, then one side should be sealed with cement paint or plaster skim.
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