Fire doors are designed to contain fire and smoke, protect escape routes and give occupants more time to evacuate safely.
But they only work when every component performs as intended.
A fire door can look fine at first glance while still containing faults that seriously reduce its effectiveness. Excessive gaps, damaged hinges or a faulty self-closer may seem minor, but during a fire they can allow smoke and flames to spread far more quickly.
At Total Fire Group, we inspect fire doors across commercial and public buildings throughout the UK. These are some of the most common failure points we find.
1. Excessive gaps
The gaps between the door and frame are crucial to its performance.
If they are too wide or uneven, smoke, heat and flames may pass through sooner than expected. Large gaps can also prevent intumescent strips and smoke seals from working effectively.
Common causes include poor installation, building movement, worn hinges, damage to the frame or the door being incorrectly trimmed.
The threshold gap beneath the door is particularly important where smoke control is required. Too much space can allow smoke to spread into corridors, stairwells and protected escape routes.
Gap sizes should always be checked against the door’s certification and specification rather than judged by eye.
2. Incorrect or damaged hinges
Fire door hinges must support a heavy door and continue to perform under extreme heat.
Common problems include loose or missing screws, damaged hinges, corrosion, incorrect hinge types or too few hinges being fitted.
Worn hinges can also cause the door to drop. This creates uneven gaps and may stop the door closing fully into the frame.
Replacing a screw or tightening a hinge may not solve the underlying issue. The hinges and fixings must be suitable for that specific fire door assembly.
3. Faulty self-closers
A fire door cannot protect a building if it is left open.
Self-closing devices should return the door to its fully closed position from any angle. They must overcome resistance from seals, latches, floor coverings and changes in air pressure.
Typical faults include:
The door stopping before it closes
The latch failing to engage
The closer arm becoming loose
The door closing too slowly
The door slamming shut
The device being damaged or disconnected
A door that closes most of the way is still a failing fire door. It must close completely without assistance.
Fire doors should never be wedged open. Where operational needs require a door to remain open, an approved hold-open or free-swing system should be considered.
4. Missing or damaged seals
Intumescent strips expand when exposed to heat, helping to seal the gaps around a fire door.
Smoke seals help restrict the movement of smoke before temperatures become high enough to activate the intumescent material.
Seals may fail because they are missing, damaged, painted over, poorly fitted or replaced with an unsuitable product.
Any replacement seals must be compatible with the door’s certification. Using the wrong product can create further compliance issues.
5. Damage to the door or frame
Fire doors often sit in busy areas and can be damaged by trolleys, equipment, deliveries and general wear.
Warning signs include cracks, holes, warping, split timber, exposed door cores, loose frames and damage around locks or hinges.
Some defects can be repaired, while others will require replacement. The damage should always be assessed by a competent person.
6. Unsuitable hardware or alterations
Locks, latches, handles, glazing and access control systems must all be suitable for the fire door.
Problems often arise when doors are altered after installation. Examples include adding new locks, drilling cable holes, cutting ventilation grilles, replacing glazing or removing closers.
Even small changes can compromise the door’s construction and invalidate its certification.
A fire door is a complete system
A fire door is more than the door leaf itself. The frame, seals, hinges, closer, latch, glazing and other components must all work together.
One defect can affect the performance of the entire assembly.
Regular, documented inspections help identify problems early, prioritise remedial work and maintain compliance.
How Total Fire Group can help
Total Fire Group supports commercial and public-sector organisations with fire door inspections, fire risk assessments, fire protection, security systems and compliance consultancy.
Our specialists can identify defects, assess risk, recommend remedial action and help establish an ongoing inspection and maintenance programme.
Fire door faults are not simply cosmetic. Addressing them early can help protect occupants, maintain safe escape routes and reduce the risk of fire and smoke spreading through your building.