Technical Booklet E Fire Safety·Page 137·5.4D
Regulation 23(2) - Materials in External Walls of Relevant Buildings
Regulation 23(2) requires that all materials in external walls and specified attachments of buildings at least 18m high containing dwellings or institutions must achieve European Class A2-s1, d0 or Class A1, with certain exemptions.
Regulation 23(2) applies to any building with a storey at least 18m above ground level and which contains one or more dwellings; an institution; or a room for residential purposes (excluding any room in a hostel, hotel or a boarding house). It requires that all materials which become part of an external wall or specified attachment achieve European Class A2-s1, d0 or Class A1, other than those exempted by Regulation 23(3).
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