Fire doors save lives — but only when they work. Most fire doors installed over the last two decades are non-compliant, often due to small changes made after installation. This 8-point check identifies the most common failures.
Look at the door edge (usually the top and both stiles) for a strip of intumescent material — a hard, resin-like strip typically 15-20mm wide. It's designed to expand when heated to seal gaps against smoke and fire.
Fail if: missing entirely, painted over so thickly it can't expand, damaged or partially removed. If you can see bare timber where the seal should be, the door has failed.
Alongside the intumescent seal, most modern fire doors have a smoke seal (typically a brush strip or fin seal) that compresses against the frame to block smoke passing when cold.
Fail if: missing, torn, permanently flattened, or not making contact when the door is closed.
Close the door and measure the gaps around it: top and stiles should be 3mm (±1mm). Bottom gap depends on threshold type: 8-10mm to solid floor is typical, but should be measured against the specific door's certification.
Fail if: gaps exceed 5mm on top or stiles, or if the bottom gap is greater than 10mm to a solid floor (no drop-seal or threshold to bridge it).
Fire doors require certified hinges — typically 100mm (4-inch) with a CE mark and fire-rating certification, and at least three per door (some certifications require four). Hinges should have intumescent hinge pads.
Fail if: fewer than three hinges, hinges without CE certification, or no intumescent pads visible.
The door should be fitted with an overhead door closer, and the closer should be strong enough to close the door from any angle including small openings. Set the door 5° open and let go — it should close and latch fully.
Fail if: no closer fitted (very common failure), closer weak enough that the door doesn't close from 5°, or closer wedged/held open.
Handles, escutcheons and letterplates on fire doors must be certified for fire use. Look for a CE mark or fire certification stamp on the underside of the plate.
Fail if: handles have been changed to non-certified aftermarket units, letterplate is not fire-rated, or escutcheons expose non-certified cylinder locks.
Fire doors require signage. Regulated buildings (HMOs, blocks, commercial) need 'Fire Door Keep Shut' or 'Fire Door Keep Locked Shut' signs on both faces. Signs should be positioned at eye level and be clearly visible.
Fail if: signage missing, incorrect wording for the door's function, or positioned where it isn't visible.
Look for physical damage: impact holes, deep sanding, unauthorised alterations (letterplates cut in aftermarket, glazing panels retrofitted). Any breach of the door core's integrity compromises the fire rating.
Fail if: holes, deep gouges, aftermarket cuts, or the door has been reduced in size (planed down significantly) to fit a warped frame.
Failed items are usually repairable — seal replacement, closer fitting, sign installation, hardware certification upgrade. Repair typically costs 10-25% of full doorset replacement.
Where the door core itself is compromised, replacement becomes necessary. Book a formal BS 8214 inspection for regulatory compliance — the 8-point check above is for internal awareness, not statutory sign-off.
