Intumescent strips or smoke seals missing or damaged in London

You open the flat door or a communal fire door and notice the black or white strip round the edge is gone. Or it's hanging off in pieces. Sometimes it's been painted over so many times it's just a solid ridge of gloss that doesn't move. On older doors you might see a fuzzy brush strip along the bottom or sides that's worn away to nothing, or missing entirely.

This is one of the most common things flagged on a fire door survey - and it's easy to miss unless you're actually looking for it, because from a couple of feet away a door with no seal looks exactly like a door with one.

What it might mean

A few things could explain it, and none of them are certain until someone's actually looked.

Strips get knocked off or peeled away during redecoration - high confidence, this happens constantly on communal doors where trades are in and out. The adhesive can also fail on its own over years, especially on older doors that have swelled and shrunk with the seasons - that one's more of a medium-confidence cause, it just wears out. And then there's paint. Someone's redecorated the landing, gone over the strip with gloss, and now it's sealed shut and can't expand the way it's meant to in a fire - again, medium confidence, but we see it a lot on Victorian and Edwardian conversion stock where doors get painted every few years and nobody thinks about what's underneath.

How urgent is it?

Same-day. A door with no intumescent strip or smoke seal isn't a fire door in any meaningful sense - it's just a door. In a fire, an unsealed gap lets flame through in minutes, and smoke gets through even faster, often before the fire itself has spread that far. That's the whole point of the seal - it's the thing standing between a contained fire and one that isn't.

If you've spotted a strip missing, damaged, or clearly painted solid, that's not a "get round to it eventually" job. Get it looked at now.

What you can safely check

You can do a basic visual check yourself before anyone comes out:

• Run your eye - and a finger, gently - along all three sides of the door where it meets the frame, checking for a continuous strip with no gaps.
• Look for a second, softer strip, usually a brush or blade seal, which handles cold smoke rather than fire.
• Check whether the strip flexes slightly or feels rigid and solid - rigid usually means it's been painted over.

Don't try to prise off paint yourself or pull at a loose strip to "test" it - you can do more damage than good, and it's not something you can properly assess without training. And don't assume a strip that's just cosmetically tatty is fine - appearance doesn't tell you whether it'll actually expand when it needs to.

What we check

A proper inspection goes further than a glance. We check the condition of the intumescent strip on both the door leaf and the frame - not just whether it's there, but whether it's the right depth and still intact along its full length. We check for a cold smoke seal and whether it's making proper contact all the way round. And we assess whether the strips fitted are original to the doorset or an aftermarket replacement - because the wrong spec on the wrong door can mean it fails outright, even if something's technically been fitted.

How it's fixed

Where the strip or seal is missing, damaged or ineffective, the fix is straightforward: intumescent strip & smoke seal fitting to the correct specification for that doorset. Where the wider door has other issues - a failing closer, damaged hinges, a leaf that's dropped - that gets picked up as part of a full fire door remedial repair, so you're not calling someone back out in three months for the next fault. As one of the fire door companies working across London's older council stock and newer developments alike, this is the single most common repair we're asked to price - because it's cheap for someone to overlook and expensive if it's never caught.

Call today if you can see daylight, gaps, or bare gloss where a seal should be - that's not a door doing its job.