BROOF (t4)
BROOF(t4) refers to the highest fire rating classification for roofs according to the European classification system BS EN 13501-5 since the national classification system BS 476-3:2004 no longer applied after 2019 and the new Approved Regulations Part B. The test indicates that the roof system prevents fire penetration for at least 60 minutes resistance to external fire spread, penetration, and burning droplets and is essential for compliance in UK building regulations, often required for flat roofs, terraces, and high-rise developments.
- No penetration of roof system within 60 minutes
- In preliminary test, after withdrawal of the test flame, specimens burn for less than 5 minutes
- In preliminary test, flame spread less than 0.38 m across region of burning
[edit] Related articles on Designing Buildings
- Blue roof.
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