Do You Need Fire Doors? The UK Rules for a Home Renovation

The honest answer to do I need fire doors in my house is that it depends on what you are about to do to it, not on how old it is or how many bedrooms it has. Most two-storey homes in London have no fire doors and need none. The moment a renovation adds a third storey, opens up a stairwell or splits a building into separate dwellings, the rules change, and they change in ways that affect joinery choices you are probably making right now.

This guide sets out when fire doors are genuinely required in a domestic renovation, what a fire doorset actually is, and the two rules that have shifted recently in homeowners' favour.

The trigger is almost always a third storey

In an ordinary two-storey house, escape works because you get down a single stair and out. Add a third storey and that stops being reliable: the route is longer, and the person furthest from the door is furthest from help. Building regulations respond by requiring the stair to be protected.

In practice, a loft conversion on a two-storey house means building control will expect a protected escape route running from the new rooms at second floor level to a final exit at ground floor, with the enclosing structure achieving 30 minutes' fire resistance and fire doors opening onto it. That includes the doors that were already there. The bedroom door on the first floor that has been perfectly acceptable for eighty years becomes part of the escape route the day the loft becomes habitable.

The other triggers are less common but worth knowing. Converting a house into flats or into a house in multiple occupation brings a different and stricter regime. Opening a stair into a kitchen or living space, which is a popular move in narrow London houses, can remove the protection the stair relied on and force a compensatory approach agreed with building control. And the door from an integral garage into the house has needed to be a fire door for a very long time.

What a fire door actually is

An FD30 doorset resists fire for 30 minutes. The important word is doorset: the rating belongs to the door leaf, the frame, the intumescent strip, the smoke seal, the hinges and the ironmongery working together. A certified leaf hung on a domestic frame with two hinges and no seals is not a fire door, whatever the label on the edge says.

Three practical points follow for anyone specifying joinery.

• The gap matters. The operating gap between door and frame is typically set at 3 to 4 millimetres. Too tight and the door binds; too loose and the intumescent strip cannot bridge the gap when it expands.
• You can usually keep the frame. Government guidance on Approved Document B notes that it should be possible to retain the existing frame when a new fire doorset goes into a loft conversion. It may need new door stops, additional fixings and proper fire-stopping around the joint with the wall, but the frame and the original architrave can often stay. In a period property that is the difference between a sympathetic job and a stripped-out one.
• Hinges and handles are part of the specification. Three CE or UKCA marked hinges rated for the door, and ironmongery that will not fail early, are not an upgrade. They are the assumption the rating was tested on.

Two rules that have changed in your favour

Self-closers are no longer needed inside a house

This is the single most useful thing for a homeowner to know. The Government's frequently asked questions on Approved Document B state plainly that door closers are no longer necessary within dwellinghouses. Nobody has to live with an overhead arm on a bedroom door, or with doors that slam in a draught. Closers can still be required in houses in multiple occupation, between private areas and the common parts.

Flats and lobby protection

The same guidance confirms that door closers are not required for internal fire doorsets in flats where those doors provide lobby protection for a common stair, with the expectation instead that the doors are kept shut, particularly at night. The flat entrance door is a different question again, governed by the block's fire strategy rather than by your renovation, and in most leases it is not yours to change unilaterally. Our guide to licence to alter for a leasehold flat covers the consent side.

The rest of the escape package

Fire doors rarely arrive on their own. On a loft conversion, expect building control to look for the whole set:

• Smoke alarms at every floor level, mains powered with a battery backup, and interlinked so that one alarm sounding sets them all off.
• Escape windows to first floor habitable rooms, with a clear opening of at least 0.33 square metres, at least 450mm by 450mm, and positioned between 800mm and 1100mm above the finished floor level.
• A compliant stair to the new storey, which is where most loft schemes lose floor area. Our guide to staircase building regulations covers the headroom and going that constrain the layout.

The window dimensions in particular are worth pinning down before you order frames. Retro-fitting an escape window into a finished elevation is expensive, and in a conservation area it can also be a planning problem.

Period property, listed buildings and conservation areas

Fire safety and heritage protection pull in opposite directions, and both are enforceable. A four-panel Victorian door is not a fire door and cannot be made into one by adding a strip. The usual routes are an upgrade specification agreed in advance with building control and, where relevant, the conservation officer, or a certified new doorset made to match the original profile and hung in the retained frame.

Start that conversation early rather than at inspection stage. If the building is listed, internal doors are very likely to be part of what is protected, and the consent process runs on its own timetable: see our guides to interior alterations to listed buildings and renovating in a conservation area.

How to handle this on a real project

Three decisions, taken in this order, prevent almost all the pain. Establish at design stage whether the scheme creates a third storey, because that single fact determines the whole door specification. Agree the approach with building control before joinery is ordered, particularly in a period house where you want to retain frames and architraves. And specify doorsets, not leaves, so the strips, seals, hinges and closers are bought as a package by one supplier who is responsible for the rating.

Our overview of building regulations for a London renovation sets out where fire safety sits among the other approvals, and how to design a loft conversion covers the layout consequences. If you want the whole scheme handled, see the rest of Vertigo Interiors.

Frequently asked questions

Do I need fire doors in a normal two-storey house?

Not as a rule. In an ordinary two-storey house, building regulations do not require fire doors on the bedrooms and living rooms. The requirement usually arrives when you change the building: a loft conversion that adds a third storey, an open-plan alteration that removes the protection the stair used to have, or a conversion into flats or a house in multiple occupation. There is one long-standing exception people forget, which is the door between an integral garage and the house.

Does a loft conversion need fire doors?

In almost every case, yes. Converting the loft of a two-storey house creates a third storey, and building control will require a protected escape route from the new rooms down to a final exit at ground floor, enclosed in 30 minute fire resisting construction with fire doors onto it. In practice that means the doors from habitable rooms onto the stairwell, on every floor, become fire doors.

Do fire doors in a house need self-closers?

No. The Government's own guidance on Approved Document B is explicit that door closers are no longer necessary within dwellinghouses. That changed a design headache into a non-issue: you no longer have to live with doors that slam or fit an overhead arm in a period hallway. Closers can still be required in houses in multiple occupation between private areas and common parts, and flat entrance doors onto a communal stair are a separate matter governed by the block's own fire strategy.

Can I keep my existing door frames?

Usually. The Government guidance notes that when a new fire doorset is installed as part of a loft conversion, it should be possible to retain the existing frame. It may need work: replacing the door stops, adding fixings, proper fire-stopping around the joint between frame and wall, and setting the operating gap correctly, which is typically 3 to 4 millimetres. In a period house that matters, because the architrave and the frame are often the parts worth keeping.

What else does building control ask for alongside the doors?

The doors are one element of an escape package. Expect mains-powered smoke alarms with battery backup at every floor level, interlinked so that one unit activating sounds them all. Habitable rooms on the first floor are expected to have an escape window with a clear opening of at least 0.33 square metres, measuring at least 450mm by 450mm, positioned between 800mm and 1100mm above the finished floor level. Design the window sizes at the drawing stage, not after the frames are ordered.

Do I need fire doors in a flat?

The internal doors of a flat are treated differently from a house, and the block's fire strategy governs the flat entrance door rather than your renovation. Government guidance states that door closers are not required for internal fire doorsets in flats where they provide lobby protection for a common stair, with the expectation that the doors are simply kept shut. Before changing anything on a leasehold flat, check your lease and the freeholder's requirements, because the entrance door is frequently outside your demise.