Do I Need Fire Doors in My House? A Plain Guide

The short answer: it depends on your stairs

English building regulations (Approved Document B) treat your staircase as the escape route. In a standard two storey house with windows in the bedrooms that can be used to escape, you are generally not required to have fire doors, though many people fit one to an integral garage or a boiler room by choice.

The moment your home has three storeys, the rules change sharply. Once there is a floor more than 4.5m above ground level, escape by window is no longer considered realistic, so the stairwell must become a protected route. That means every habitable room opening onto the stairs needs a fire door, and that includes the kitchen, the lounge and each bedroom on every level.

Loft conversions are the most common trigger

This is what brings most Croydon and Purley homeowners to us. Converting a loft on a two storey house creates a third storey, which retrospectively puts the whole staircase in scope. Homeowners are often surprised that the ground floor lounge door now needs replacing as well as the new loft door.

There is an alternative if you cannot bear losing every original door: a sprinkler system or an open plan compensatory design can sometimes reduce the requirement. Discuss this with your building control body or approved inspector early, because it affects the layout drawings, not just the ironmongery.

Flats, HMOs and rented property

Flats are a different matter. The entrance door to a flat in a shared block should be an FD30S fire door, self closing, with intumescent strip and cold smoke seal. In Croydon's many converted Victorian houses, the original four panel door is very often the flat's front door and simply is not compliant, however solid it feels.

Landlords and HMO licence holders have separate duties. Croydon Council operates licensing schemes for houses in multiple occupation, and fire door condition is routinely inspected. Since 2023 the Fire Safety (England) Regulations have also required responsible persons in blocks above 11m to carry out quarterly checks of communal fire doors and annual checks of flat entrance doors.

What actually makes a door a fire door

A fire door is a certified assembly, not just a heavy leaf. Certification covers the door, the frame, the hinges, the seals and the closing device together. Fitting a certified FD30 leaf into an old frame with two hinges and an 8mm gap gives you very little.

Points that fail inspection most often:

• Gaps over 4mm at the top and sides (3mm is the usual target); around 8mm to 10mm at the threshold
• Intumescent strip missing, painted over or cut short
• Only two hinges where three CE marked hinges are needed
• Doors trimmed too much at the bottom, past the manufacturer's permitted tolerance
• Hardware such as letterplates or spyholes cut in without a fire rating
• Closers removed or wedged open where self closing is required

Realistic costs and how to plan the work

As a rough guide, a supplied and fitted FD30 door on a domestic landing typically lands somewhere in the £350 to £650 range depending on finish, ironmongery and whether the frame and lining need replacing. Solid painted doors sit at the lower end, veneered or glazed and heritage style panelled doors at the higher end. Flat entrance doorsets with a certified frame and hardware are a bigger job again.

If you are mid conversion, order early. Lead times on certified doorsets and on matching four panel styles for period properties can run to several weeks, and building control will not sign off the conversion without them.