If you’ve ever noticed a heavy door with a blue “Fire Door Keep Shut” sign, you’ve likely come across one of the most important passive fire protection tools in any building: the fire door.
But what exactly is a fire door, how is it different from a regular door, and why does it matter so much for safety and compliance? In this blog, we’ll break it all down in simple terms.
Fire Doors Save Lives
A fire door is a specially constructed door that is designed to resist the spread of fire and smoke for a set period of time—typically 30 minutes (FD30) or 60 minutes (FD60). When installed correctly, a fire door helps:
- Contain fire and smoke in one area
- Protect escape routes such as corridors and stairwells
- Give people more time to evacuate
- Minimise damage to the rest of the building
They play a crucial role in any building’s compartmentation strategy, working alongside fire-resisting walls, ceilings, and floors to slow down the spread of a fire.
What Makes a Fire Door Different?
Unlike standard doors, a fire door is made from fire-resisting materials and built to specific standards. Some key features include:
- Solid core construction (not hollow)
- Intumescent strips in the frame or door edge, which expand when exposed to heat and seal gaps
- Cold smoke seals to prevent smoke leakage
- Self-closing mechanisms to ensure the door closes after each use
- Fire-rated hinges, locks, and hardware
- Certification labels or markings (often found on the top edge or side)
It’s not just about the door itself—it’s the complete assembly, including the frame and all fittings, that must be tested and certified as a unit.
Where Are Fire Doors Required?
Fire doors are required in many different types of buildings in the UK, including:
- Blocks of flats: Protecting stairwells, communal corridors, and flat entrances
- Houses in multiple occupation (HMOs): Between bedrooms, kitchens, and escape routes
- Commercial buildings: Between offices, storerooms, kitchens, and escape routes
- Schools, hospitals, and public buildings: To compartmentalise risk and protect escape routes
Your fire risk assessment, carried out under the Regulatory Reform (Fire Safety) Order 2005, should identify exactly where fire doors are needed in your building.
How Are Fire Doors Rated?
Fire doors are given an “FD” rating based on the number of minutes they are certified to resist fire. The most common types include:
- FD30 – resists fire for 30 minutes
- FD60 – resists fire for 60 minutes
- FD120 – for high-risk environments like plant rooms or large buildings
It’s important that the door’s certification matches the risk level and location.
Do Fire Doors Need Maintenance?
Yes—and more than many people realise.
Under UK fire safety regulations, all fire doors must be:
- Inspected regularly to check for damage, wear, or faults
- Maintained in good working order, including closers, seals and hinges
- Repaired or replaced if compromised in any way
Even small gaps, missing seals, or poor installation can seriously reduce a fire door’s effectiveness. That’s why regular fire door inspections—ideally carried out by a competent person—are essential.
How Can You Tell If a Door Is a Fire Door?
Look for:
- A certification label or plug (usually at the top or side edge)
- Intumescent strips in the frame or door edge
- A “Fire Door Keep Shut” sign
- Self-closing mechanism in working order
If in doubt, ask a professional to inspect it. At ESI, we routinely inspect and report on fire door compliance as part of our fire safety services.
Fire Door Safety in Practice
A fire door is only effective if it:
- Closes fully under its own power
- Is not wedged or propped open
- Is kept in good condition
- Is suitable for its location and fire risk
Using a fire door as a regular door—with signs of wear, paint over seals, or makeshift alterations—can turn it into a liability.
Fire Door Support from ESI
At ESI: Electrical Safety Inspections, we help building owners and managers across Farnborough, Camberley, Reading, Guildford, and the surrounding areas keep their fire doors up to standard.
We offer:
- Fire door inspections and reporting
- Advice on replacements and upgrades
- Support for HMOs, flats, commercial buildings and more
- Guidance on your responsibilities under UK fire safety law
Not sure whether your doors are compliant? We’ll take the guesswork out of fire door safety.
Get in touch with ESI today to arrange a professional fire door check and keep your building protected.
