Fire door gaps and hinges
Too much gap lets the smoke through, and it is often the hinges that caused it.
Get a priceTake a £1 coin. It is a bit under 3mm thick.
The gap down the side and across the top of a fire door should be somewhere between 2mm and 4mm. If two coins slide in together, the door has a problem.
On a failed report we usually see 5mm or 6mm down the lock side and nothing at the top hinge. That means the door has dropped.
Why they drop
Worn hinges are the common reason. The steel wears and the bearings go.
Then missing screws. We keep finding hinges held on by two screws out of eight because the others stripped and nobody went back. The top hinge carries most of the weight, so it loosens first.
A hinge torn out of its recess is worse, because the timber behind it has split. We cut it back and let in new hardwood so there is something solid to fix into.
Small fixes
If the door is only slightly out, new hinges or a packer behind one can pull it back. That is under an hour for a carpenter.
A door that is too tight can be eased, but only so far. How much can come off an edge is set by its certificate, and we stop well short of it.
Bigger fixes
Sometimes it is the frame. The gap is wide at the top on one side and tight at the bottom on the other.
That means off with the architraves, pack and fix the frame again, foam behind it with fire-rated foam, and put it all back. Two people and most of a day. We price it as its own line, because calling it a quick adjustment is how jobs go wrong.
Too wide all the way round? Then the door has shrunk, or it was cut badly when it was hung. We add hardwood lippings to bring the edge back, if the certificate allows it.
The bottom gap
The bottom edge has its own limit. Around 8mm is common on a standard door, tighter where the door has to hold smoke at floor level. Your certificate decides. A new carpet can change the reading overnight.
Hinges we use
Steel butt hinges tested for fire doors, normally Grade 13 to BS EN 1935. At least three to a leaf, every screw in. Brass and cheap decorative hinges can soften or melt in a fire, so they come off.
Questions we get asked
Can I fill a big gap with sealant?
No. Sealant in the gap is a common fail. The door gets adjusted, rehung or lipped.
Do you take the door away?
Rarely. Most of it is done on trestles on the landing.
Send it to us with the postcode and we will price it door by door.
Get a price