A composite fire door is a doorset built with a fire-resisting core and a tough skin, often GRP, that has been tested and certified as a complete assembly. Composite fire doors are popular for flat entrances because they need little maintenance and come in a wide range of colours.
Where do composite fire doors make sense?
Composite doorsets are widely used as flat entrance doors, both inside corridors and on external deck-access walkways where the door faces the weather. Their factory finish avoids repainting, which matters because paint build-up is a common reason seals stop working. Many products also offer security features alongside the fire rating.
What to check before you buy
Composite doors vary widely. The certification must cover the whole doorset as supplied: the core, skin, frame, glazing, letterplate, viewer and every item of hardware. Ask to see the certificate and the installation instructions, and check that the door's configuration, such as a side panel or glazed panel, is actually covered. BS 8214:2026 now includes maintenance guidance for composite and metal doors, reflecting how common they have become.
How we fit composite doorsets
Composite doorsets are installed strictly to the manufacturer's instructions, which typically set out fixing positions, packing, the sealing of the frame-to-wall gap and threshold details. We set the closer so that it closes and latches the door, test the locks and record everything for your files. Where a resident or freeholder chooses colours, we make sure the chosen option is within the certified range.
Specification at a glance
- Typical rating
- FD30S / E30Sa
- Construction
- Fire-resisting core with composite skin
- Use
- Internal corridor or external deck access
- Finish
- Factory colour, low maintenance
- Security
- Multi-point or mortice options within evidence
- Maintenance
- Covered in BS 8214:2026 guidance
What's included
- Advice on certified composite products and options
- FD30S composite doorset made to measure
- Self-closer, smoke and intumescent seals
- Viewer, numerals and security hardware within evidence
- Weather detailing for external deck-access doors
- Certificate reference and photo record
How the installation runs
- Survey opening, threshold and exposure
- Agree colour, glazing and hardware within the certified range
- Order doorset to measure
- Remove existing door and frame
- Install, seal and adjust to the manufacturer's instructions
- Test closer and locks and hand over evidence
How much does it cost?
£1,400 – £2,600 ex VAT
£1,400–£2,600 per composite flat entrance doorset supplied and fitted, ex VAT. These are guide figures; your price is fixed after a free survey. See all guide prices or try the guide-price tool.
Questions about composite fire doors
Are composite fire doors as good as timber ones?
Both can perform well when they are certified and installed correctly. Composite doors offer low maintenance and colour choice; timber doorsets offer more flexibility on sizes and finishes. The certification and installation matter more than the material.
Can composite fire doors face the weather?
Some are designed for external use on deck-access blocks. The product must be certified for that use and fitted with the right threshold and weather detailing.
Can I add a letterbox to a composite fire door?
Only if the letterplate is part of the certified doorset. Cutting one in afterwards would compromise the door's fire performance.
Do composite fire doors need a closer?
Yes, as flat entrance doors they need a self-closing device that closes and latches them. This can be overhead or concealed, depending on the certified options.