Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings·Page 58·3.58
Performance standards for windows, roof windows, rooflights and doors
Windows, roof windows, rooflights and doors must be draught-proofed units with area-weighted average performance meeting Table 3.2 standards. When replacing controlled fittings, insulated cavity closers should be provided where appropriate.
Where windows, roof windows, rooflights or doors are to be provided, they should be draught-proofed units whose area-weighted average performance is no worse than that given in Table 3.2. When replacing controlled fittings, insulated cavity closers should be provided where appropriate.
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