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Building Regulation Approved Document B (Fire Safety) roof classifications are to a European test system whereby whole roof constructions are measured for penetration and surface spread of flame. BROOF[t4] is the highest classification, FROOF[t4] is the lowest.
Transposition between the European test system and older national classifications can be seen in Table B2 in Approved Document B – Volumes 1 and 2. Regarding the highest classifications;
Where AC was previously the minimum level of external fire performance deemed acceptable, there were always specifiers who required improved fire performance and it should be appreciated that UK Building Regulations now seek this too, by means of:
Constructions with exposed waterproofing tested to the European system
Constructions with covered waterproofing that do not require testing
When protected by an inorganic covering (e.g. gravel or paving slabs) listed in the Annex of Commission Decision 2000/553/EC, a flat roof waterproofing membrane is deemed to achieve a BROOF(t4) classification and so is unrestricted by the national Building Regulations with respect to proximity to a boundary.
Siltec are proud to have an extensive range of tested systems that can provide the highest BROOF(t4) performance classification for potentially hundreds of flat roof permutations that include single ply, liquid, hot melt, and bituminous waterproofing. This provides our clients with a full range of solutions whilst still complying with HM Government Building Regulations.
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A further directive of Approved Document B is the requirement to use non-combustible materials for flat roof applications in certain circumstances, in addition to BROOF(t4) classified fire performance. For these applications, Siltec can provide a wide range of non-combustible systems and ancillaries including:
Take a look at some of the common questions we get asked by our customers here at Siltec.
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Flat roofs constructions, including the deck, are subject to external fire spread. When a flat roof construction is tested for its external fire performance (penetration through the roof construction and surface spread of flame), it is classified within the European system as highest BRoof(t4) through to lowest FROOF(t4).
Not all flat roofs can be classified, such as existing roofs. Some do not need to be classified due to their inherent ability to stop external fire spread, such as gravel and paving slab finished inverted roofs and protected roofs, so use is unrestricted.
With tested roofs however, Siltec are proud to have an extensive range of tested systems that can provide the highest BROOF(t4) performance classification for potentially hundreds of flat roof permutations that include single ply, liquid, hot melt, and bituminous waterproofing. This provides our clients with a full range of solutions whilst still complying with HM Government Building Regulations.
