Fire door gaps
Fire door gaps that are too wide or uneven are one of the most common faults I find. A wide gap lets fire and smoke past the door. If you're not sure about yours, book an inspection or call me.
The usual target
The gap on the sides and head is usually about 3 mm, between 2 mm and 4 mm. The door's certification and the manufacturer's instructions set the tolerance for each door, and I judge it against those.
The threshold gap
The bottom gap is checked separately from the sides and head. I assess it against the door's certification and the manufacturer's instructions, along with how smoothly the door swings and whether it closes fully.
How I measure
I measure round the leaf with feeler gauges, on every side, and photograph any gap that is out of tolerance. Uneven gaps often come from a dropped hinge or a frame that has moved.
What fixes a gap
A minor door adjustment costs £45 to £75. New fire and smoke seals cost £55 to £90. If the leaf can't be brought back within tolerance, a new FD30 leaf in a suitable existing frame costs from £250 to £400. All of these are plus VAT, and inspection prices are on the Fire door inspection cost page.
When a gap fails a door
A door fails when its gaps are too wide or too uneven for its certification. The report lists every failed door with photos and what needs fixing. See Fire door inspection and survey in Birmingham for how the visit works.
Price your inspection
Over 60 doors? Call me for a site price
8 doors · £120 + 5 × £20
plus VAT (£264 including VAT)
Book at this priceGet your fire door gaps measured
Tell me how many doors there are and send photos of any gaps you're worried about. I'll quote before the visit.