What Are Fire Doors Made Of?

When it comes to fire safety, fire doors are one of the most effective ways to slow the spread of flames and smoke throughout a building. But what exactly are fire doors made of, and how do the materials used impact performance?

In this blog, we take a deeper dive into the different types of fire doors and their construction, and explain the benefits of each. Whether you’re managing a commercial premises, overseeing a housing development, or you’re involved in refurbishments, you’ll have a better understanding of the materials that make up an effective fire door, helping you make an informed and compliant choice.

Common fire door materials and their benefits

Fire doors are constructed using a variety of materials, each offering different levels of fire resistance, durability, and suitability depending on the building type and risk profile.

Here are the most common fire door materials and the advantages they bring in terms of safety, performance, and compliance.

Wooden fire doors

Wooden fire doors are one of the most commonly used types, particularly in residential buildings, offices, schools, and communal areas of apartment blocks. These doors are typically constructed with a solid core made from materials such as chipboard, particleboard (both of which are ideal for internal use), or solid timber (perfect for external applications), and encased in a hardwood veneer.

Most wooden fire doors are certified to provide either 30 minutes (FD30) or 60 minutes (FD60) or fire resistance. When properly installed with intumescent strips and appropriate hardware, they help contain fire and smoke long enough to enable safe evacuation and limit structural damage.

Timber fire doors also offer aesthetic flexibility, allowing them to blend into modern and traditional interiors without compromising fire safety. However, their performance depends heavily on installation quality and third-party certification.

Steel fire exit doors

Steel fire exit doors are commonly found in industrial buildings, warehouses, and commercial units where durability, high foot traffic, and security are essential. These doors are made using galvanised or stainless steel skins filled with a fire-resistant core, such as mineral wool or honeycomb.

Steel fire doors are typically used as fire exits or for back-of-house access routes and are often rated for FD60, FD90, or even FD120, providing a high level of resistance to fire and smoke spread. They’re ideal for areas prone to impact, vandalism, or exposure to harsh conditions.

While less customisable in appearance than timber doors, steel fire exit doors are low maintenance, highly robust, and often combined with panic hardware for emergency use.

Composite fire doors

Composite fire doors combine the strengths of several materials to deliver high performance in both fire resistance and energy efficiency. Typically made with a solid timber core and layered with fibreglass, uPVC, or steel skins, these doors are reinforced with fire-resistant and insulating materials.

Composite fire doors are increasingly used in housing developments, student accommodation, and modern commercial buildings. They offer improved thermal performance and durability while meeting FD30 or FD60 fire resistance requirements.

Because of their construction, composite doors are an ideal choice for external applications because they can be manufactured with a range of surface finishes, colours, and designs, making them an attractive option without compromising fire safety.

Glazed fire doors

Glazed fire doors are designed to provide both safety and visibility, commonly used in corridors, stairwells, and reception areas where maintaining sightlines is important for evacuation and supervision.

These doors incorporate fire-rated glass, such as Pyrobel, Georgian-wired, or clear intumescent glazing, into the timber or steel door leaf. The glass used in glazed fire doors must meet strict testing standards and remain intact under fire conditions for a specified time – usually 30 or 60 minutes.

Glazed fire doors combine functionality with aesthetic value and help maximise natural light while ensuring compliance with fire regulations. They must be properly fitted with intumescent glazing seals and compatible framing systems to ensure their integrity during a fire.

How does the type of fire door material affect performance?

The choice of fire door material has a direct impact on its fire resistance rating, durability, and maintenance needs. While timber and composite fire doors are widely used in residential and light commercial settings, steel fire exit doors are favoured for industrial and high-risk premises due to their greater resistance and structural strength.

All certified fire doors must meet fire resistance classifications such as FD30, FD60, FD90, or FD120, indicating the number of minutes they can withstand fire exposure. The material must also be compatible with other fire door components, including:

• Intumescent seals, which expand to fill gaps around the door when exposed to heat
• Fire-rated hinges, closers, and locks, which maintain integrity under fire conditions
• Glazing systems (where applicable) that prevent heat transfer and smoke passage

A correctly specified and professionally installed fire door system ensures that the materials work together as a whole to delay fire spread and support safe evacuation.

What are the current fire door regulations?

In the UK, fire door compliance is governed by a number of key standards and regulations. These ensure that all fire doors installed in commercial or multi-occupancy buildings are properly manufactured, installed, and maintained.

Key fire door regulations and standards include:

• The Regulatory Reform (Fire Safety) Order 2005 – this places responsibility on the ‘responsible person’ to ensure fire doors are adequate and maintained.
• BS 476-22 – this is the British Standard for fire resistance of non-loadbearing elements, including doors.
• BS EN 1634-1 – this is the European Standard for fire resistance testing of doors and shutter assemblies.
• Building Regulations: Approved Document B – this provides guidance on fire safety in the design and construction of buildings in England and Wales.

All fire doors must be installed by competent, qualified individuals and should be third-party certified – for example IFC Certified – a certification we’re proud to hold here at Fire Industry Specialists (FIS) Ltd.

How to choose the right fire door material for your premises

Choosing the best fire door material depends on several factors which will be unique to your property and its usage. Some factors to consider include:

• Building type and layout – a large commercial premises or warehouse may benefit from steel fire exit doors, while residential developments may prefer composite or wooden fire doors.
• Level of risk – high risk environments like plant rooms or escape routes require longer fire resistance and tougher materials.
• Aesthetic and architectural design – in office spaces or hospitality venues, veneered timber or glazed fire doors may offer a better visual fit.
• Maintenance capacity – you’ll want to consider how often your fire doors will be used and whether they’ll be exposed to wear, moisture, or damage.
• Regulatory compliance – you should always ensure your chosen fire door type meets the required FD rating, comes with test evidence, and is installed by a competent contractor.

A professional fire door survey can help you assess these factors and determine the best material and configuration for your fire safety strategy.

We can provide certified fire doors for your business

By understanding what fire doors are made of, you’re equipped with the knowledge to make an informed decision on the correct door type for your property. Whether you opt for steel, composite, glazed, or wooden fire doors, each door must be selected and installed with care while taking into account your building’s structure, purpose, and fire risk.

At FIS Ltd, we can supply and install high-quality fire doors – including timber, steel, composite, and glazed fire doors – for commercial and multi-occupancy buildings across the UK. Our team will offer expert guidance and third-party certified solutions to meet your legal obligations.

As part of the LS Fire Group, we can deliver end-to-end support – from fire door surveys and design, to supply and installation – in full compliance with UK Building Regulations, British Standards, and fire safety legislation.

Don’t hesitate to get in touch with us today to discuss your fire door requirements and get a tailored quote from your premises.