FD30 vs FD60

Most internal residential doors only need an FD30 rating. FD60 is typically required at doors onto protected stairways in buildings above 11 metres, at doors separating high-risk rooms (plant rooms, fuel stores), and where the building's fire strategy specifies it. Always check the fire risk assessment or the architect's door schedule — substituting FD30 where FD60 was specified can fail building control sign-off and the Building Safety Regulator's inspection.

For flat entrance doors in low-rise buildings (under 11m), an FD30S (with smoke seals) is the standard requirement. For flats in buildings over 11m, the door must still be tested to BS 476-22 or BS EN 1634-1 and the building owner must keep documented inspection records under the Fire Safety (England) Regulations 2022. Some freeholders specify FD60 by default for the whole block to simplify management.

No. Fire ratings are based on the complete tested door assembly — the leaf, frame, seals, hinges, closer, and any glazing. Adding more intumescent strip to an FD30 door does not give it FD60 performance and will not be accepted by building control or insurers. If you need FD60 performance, the entire assembly must be FD60-certified from the factory.

FD60 doors typically carry a 30-50% price premium over their FD30 equivalents because the cores are thicker and denser, more substantial intumescent seals are used, and the supporting hardware (hinges, closers, frames) must also be FD60-rated. For high-risk buildings or stairwell enclosures the additional cost is non-negotiable; for general internal applications, FD30 is the more cost-effective choice.

Smoke seals are denoted by an "S" suffix on the rating — FD30S and FD60S. Most modern fire doors are supplied as FD30S or FD60S by default because the Building Regulations require smoke control on flat entrance doors and on most internal fire doors in residential buildings. Smoke seals (brush or fin) prevent cold smoke leakage, which is a separate hazard from the heat of the fire itself.