Technical Booklet G Resistance to the Passage of Sound·Page 89·3.129
Floor voids sealing for separating wall type 4 – timber frames with absorbent material
Spaces between floor joists perpendicular to the wall must be sealed with full-depth timber blocking, with any remaining voids filled with flexible caulking.
Where the joists are at right angles to the wall, spaces between the floor joists should be sealed with full depth timber blocking. Any voids to be filled with flexible caulking.
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