Rating language
What do FD30 and FD60 mean?
In common UK usage, FD30 and FD60 describe timber-based door assemblies intended to provide at least 30 or 60 minutes of fire-resistance integrity under the relevant evidence. Higher periods can be specified where the design requires them.
The rating applies to the represented doorset configuration. It should not be inferred from thickness, colour, weight or a label alone.
| Common description | Broad meaning | Do not assume |
|---|---|---|
| FD30 | Nominal 30-minute integrity classification | That smoke leakage is also controlled |
| FD30S | FD30 with the required smoke-control performance | That any brush seal or threshold gap is acceptable |
| FD60 / FD60S | Nominal 60-minute integrity, with S adding smoke control | That FD30 components can simply be reused |
| E / EI classifications | European integrity and, where stated, insulation classification | Direct equivalence without checking the specification |
Design decision
Who decides the required rating?
Approved design information, the fire strategy, compartmentation plans and applicable guidance establish the intended performance. A fire risk assessment may identify missing evidence or an unsuitable condition, but should not invent a rating without understanding the building.
When a replacement is proposed, confirm the wall, opening, door use, dimensions, glazing, hardware, smoke requirement and certification route. A more highly rated leaf is not automatically a safe substitute if the rest of the arrangement is incompatible.
- Locate the door on the compartment or fire-strategy drawings
- Confirm integrity and smoke-control objectives
- Check supporting wall and permitted configuration
- Specify the complete doorset and hardware
- Retain installation, inspection and maintenance evidence
Correct interpretation
Why the minute rating is not a real-fire stopwatch
Standard testing enables products and systems to be compared under controlled exposure. Real fires vary in fuel, ventilation, pressure, geometry, damage and firefighting intervention. The result therefore supports design; it does not promise an exact safe waiting time.
A door that is wedged open, does not latch, has incompatible glazing or is badly installed may not provide the expected barrier regardless of the stated rating.