Technical Booklet E Fire Safety·Page 118·Diagram 4.5, para 4.35 4.36(a), 4.39 4.40(a) and Table 4.6 Items 1, 3 & 4
Cavity walls excluded from certain provisions for cavity barriers
Diagram showing external cavity walls of masonry construction where cavity barriers are not required at certain locations if the wall meets specified dimensions.
External cavity wall of two leaves of brick, block or concrete each at least 75 mm thick – cavity width 300 mm maximum. Cavity barrier at top of wall (unless cavity is totally filled with insulation). Cavity barrier around opening.
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