Do I need special door frames for fire doors?
The practice of ‘knocking up’ a door frame on site or in a workshop, hanging a door and believing that the result constituted a valid fire door installation was never correct.
Door frames should be purchased from the door manufacture, or from a company licensed to manufacture them or via a BWF Approved Fire Door Centre.
- 60 minute fire doors - Frames should be made of hardwood with a density greater than 650 kg/m3
- 30 minute fire doors– frames or linings can be made of softwood, with a minimum density of 450 kg/m3 (or to match the density and frame dimensions given in the manufacturers’ installation instructions)
You should check the suitability of different timber species for doorframes with the door manufacturer, since some materials such as Ash are NOT RECOMMENDED by many door manufacturers.
How is a door stop installed?
Door stops, which assist the door in latching - can be cut out of the solid frame (a rebate is produced to form a stop for the door) or 'planted'.
The planted section should be fixed by pinning, or gluing and pinning the stop to the frame.
How thick should my fire door frame or lining be?
Frame or lining thickness would usually be tested at a minimum 30 mm (finished size, excluding stops) or the thickness given in the manufacturers’ installation instructions, to ensure hinge screws hold securely.
Can I use the existing door frames or MDF?
MDF or chipboard frames and linings are permitted by SOME door manufacturers where test evidence allows. The use of MDF or chipboard may NOT always apply to every door in the manufacturer’s range.
What considerations are there for the supporting construction for a fire door frame?
The frame or lining should be constructed into a brick, block or masonry wall or an appropriate timber stud/plasterboard lined partition capable of being equal to the rating of the door assembly. Any voids between the frame / lining and the wall should be infilled with mineral fibre or intumescent paste. In the case of FD 60 doors (or higher) : refer to Table 3 : BS 8214 1990.
Do I fit seals into the frame or door?
ALL fire doors MUST be fitted with the appropriate seals. Where possible, the seals should be fitted to the frame.
Intumescent seals MUST be used as recommended by the door leaf manufacturer.
Can I use an existing door frame or must I always use a new one?
There may be circumstances where fitting new frames is not possible or practicable.
The thickness of the existing frame should be checked to ensure it meets the requirements of the installation instructions, and guidance sought if undersize.
In these situations, it may be more practicable to fit intumescent seals into the door edge* if grooving the frame is difficult.
* Care must be taken to ensure the fire door label is not damaged
What gaps are required around a door and its frame?
The gap between the door and the frame is extremely important and must be suitable for the intumescent seal fitted.
In general the gap should not exceed 3mm along the 2 long edges and across top of the door leaf – to facilitate checking of the gap on site, a BWF-CERTIFIRE Scheme GapTester is available on request providing you send through your name, address and the number of Gap Testers that you require.
The gap at the bottom of the door is usually around 10mm* for non-smoke conditions BUT 3mm when smoke seals are required.
* Check the door manufacturer’s instructions