Technical Booklet G Resistance to the Passage of Sound·Page 40·2.63
Prohibited Practices for Cavity Masonry Separating Walls
Specific construction practices that should be avoided when building cavity masonry separating walls to prevent degrading sound performance.
Do not (g) Do not try and convert a cavity separating wall to a type 1 (solid masonry) separating wall by inserting mortar or concrete into the cavity between the two leaves. (h) Do not change to a solid wall construction in the roof space as a rigid connection between the leaves will reduce wall performance. (i) Do not build cavity walls off a continuous solid concrete slab floor. (j) Do not use deep sockets and chases in the separating wall, do not place them back to back.
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