A plain-English guide to fire door ratings, seals, glazing and the situations where they are required.
Short answer: an FD30 fire door is tested to hold back fire for 30 minutes, which is the rating used in most homes. You typically need them when a loft conversion adds a storey, in houses in multiple occupation, and in certain other property types, but a fire door only works if it is fitted correctly with the right frame, gaps, seals and hardware.
That last point is the one people overlook. A certified door hung badly in an old frame will not perform as tested.
The FD number is the time in minutes the door assembly resisted fire in testing. FD30 gives 30 minutes, enough time to get out of the building in most domestic layouts. Higher ratings exist but are more common in commercial and communal buildings.
Smoke usually spreads faster than flames. Intumescent strips in the edge of the door or frame expand when heated and close the gap, and smoke seals limit the passage of cold smoke in the early stages. Both are part of what makes the door a fire door.
Common domestic situations include:
Most manufacturers set limits on the gap around the door, the type of hinges and the ironmongery that can be used. Cutting a door down too far, fitting the wrong hinges or adding an unrated letter plate can invalidate the rating. Complete fire door sets, which supply the door, frame and ironmongery together, remove much of that risk.
Vision panels are allowed as long as the glass and the glazing system are fire rated. They are useful for letting light into hallways and landings, and on doors where you want to see who is on the other side.
Fire doors should close fully on their own where a closer is fitted and should never be wedged open. Check periodically that the seals are intact and that the door has not dropped on its hinges.
Landlords of houses in multiple occupation and some other rented homes have specific fire safety duties, which often include fire doors to bedrooms and kitchens along with the escape route. Local councils and fire services publish guidance for landlords, and a fire risk assessment will usually set out what is needed for a particular property. Keeping records of the door certification, fitting and later checks makes inspections far more straightforward.
We supply and fit certified fire doors and complete door sets. Send us the details and we will quote.
FD30 means the door assembly resisted fire for 30 minutes in testing. It is the standard rating for residential properties.
Usually yes. Where a loft conversion creates a new storey, Building Regulations typically require protected escape, which often means fire doors onto the stair. Building control will confirm for your project.
Yes, provided the glass and glazing system are fire rated. Glazed fire doors are common where light transfer between rooms is wanted.
It depends on the frame and the door's certification. A complete fire door set with a matching frame and ironmongery is the most reliable way to keep the rating valid.