BROOF, DROOF, CROOF and FROOF

BROOF, DROOF, CROOF and FROOF refer to different fire rating classifications for roofs according to the European classification system BS EN 13501-5 from the highest to the lowest rating since the national classification system BS 476-3:2004 no longer applied after 2019 and the new Approved Regulations Part B.

BROOF(t4): Refers to the highest rating and indicates the roof system prevents fire penetration for at least 60 minutes and restricts flame spread. It inticates superior 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

CROOF(t4): The intermediate rating which indicates no fire penetration within 30 minutes, with limited flame spread.

• No penetration of roof system within 30 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

DROOF(t4): The lower rating indicates the system is penetrated within 30 minutes in certain tests, but not in others.

• Roof system is penetrated within 30 minutes but is not penetrated in the preliminary test
• 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

EROOF (t4)

• Roof system is penetrated within 30 minutes but is not penetrated in the preliminary test
• Flame spread is not controlled

FROOF(t4): The lowest rating.

• No performance determined

The Independent Review of Building Regulations and Fire Safety, that followed the Grenfell fire, chaired by Judith Hackitt, reviewed the Building Regulations 2010, and concluded that a more robust regulatory system was neede. As a result the Building (Amendment) Regulations 2018 were issued. The most significant change being the complete ban of combustible materials in external walls and the Approved Document B (ADB) on fire safety, which affected roofing. This is where national classification system BS 476-3:2004, no longer applies but replaced by the European classification system BS EN 13501-5 and the five European class ratings: BROOF(t4), CROOF(t4), DROOF(t4), EROOF(t4) and FROOF(t4).

[edit] Related articles on Designing Buildings

• Blue roof.
• Cold roof.
• Designing out fire risk in roof voids.
• Existing guidance on fire compartmentation in roof voids.
• Flat roof.
• Green roof.
• Metal roofing.
• Pitched roof.
• Shingle roofing.
• Slate roofing.
• Solar panels, pitched roofs and risk of fire spread.
• Tile roofing.
• Thatch roofing.
• Types of roof.
• Warm roof.