Technical Booklet E Fire Safety·Page 135·5.4

Materials and Products for High-Rise Buildings

Insulation and filler materials used in external walls of buildings with a storey 18 m or more above ground level must be Class A2-s3, d2 or better, except for masonry cavity wall construction complying with Diagram 4.5.

Where a building has a storey the floor of which is 18 m or more above ground level, any insulation material, and any filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) used in the construction of an external wall should be Class A2-s3, d2 or better. This restriction does not apply to masonry cavity wall construction which complies with Diagram 4.5 in Section 4. Where Regulation 23(2) applies, that regulation prevails over all the provisions in this paragraph.

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