Glazed Fire Doors: Costs, Glass Types and Specification

How much does a glazed fire door cost?

Expect fire-rated glazing to add roughly £200 to £800 + VAT per door over a solid door. Integrity-only glass sits at the lower end, insulating glass and large panels at the top.

The cheapest route is almost always a doorset ordered with the vision panel already fitted at the factory. Cutting a panel into an existing door on site costs more, and many doors do not allow it. See fire door cost, supply and fit for full doorset prices.

What types of fire-rated glass are there?

There are two main groups: integrity-only (E) glass, which stops flames and smoke, and integrity and insulation (EI) glass, which also blocks radiant heat.

Within those groups the glass itself varies. The right choice depends on the fire strategy, where the door is and who walks past it.

Do I need E or EI fire glass?

E glass suits most vision panels. Approved Document B limits how much integrity-only glass can be used on some escape routes, and EI glass is needed where the fire strategy calls for insulation.

Under Approved Document B, if glazing meets both integrity and insulation there is no limit on how much glass you can use. Integrity-only glass is restricted in size and position on certain escape routes, such as protected stairs, because people passing it would be exposed to radiant heat. The fire strategy or fire risk assessment should say which applies to each door.

Can you add a vision panel to an existing fire door?

Only if the door's certification allows it, and the work is done to the tested glazing system. Many fire doors do not allow it.

Each certified door is tested with set panel sizes, positions, glass types, beads and glazing seals. Cutting an aperture outside that scope voids the door's evidence. Where it is permitted, the work should be done by a competent person who records the glass and system used. Where it is not, a new glazed doorset or a new leaf in the existing frame is the answer. See flat entrance fire door replacement.

How can you tell if fire door glass is fire rated?

Look for a permanent mark etched in the corner of each pane naming the manufacturer and product. If there is no mark, the glass cannot be confirmed as fire rated.

This is a common fault. In our inspections, 5% of 448 itemised doors had glazing that could not be confirmed as fire rated. In one hotel, 20 doors on escape routes had glazing we could not confirm. The figures are on our fire door inspection statistics page.

The usual cause is an earlier repair with ordinary float glass, or the right glass held in with the wrong beads or no intumescent glazing seal. The government's 2025 fire door guidance says glazing, including side and over panels, should keep its ability to resist fire and smoke. Our fire door inspection checklist covers glazing alongside the other checks, and failed panels can be put right as part of fire door repairs.

• An etched mark on each pane, readable from one side.
• Beads fixed as the door's certification shows, usually with fire-rated glazing seals.
• No cracks, gaps or loose beads.
• Glass type recorded in the door schedule for each door.

Do glazed fire doors in schools need safety glass too?

Yes, where the glass is low down. Approved Document K treats glass in a door between floor level and 1,500mm as a critical location that needs safety glass.

In schools, nurseries and busy public buildings the glass has to meet both a fire rating and an impact class under BS EN 12600. Some fire glasses do both. Others need a laminated layer added, which pushes the cost towards the top of the range. Plain Georgian wired glass is not a safety glass, so it should not be used in low-level panels unless that product has been tested for impact.

We inspect and repair fire doors across Bedfordshire, Hertfordshire, London, the Thames Valley and the East Midlands.

Sources

• GOV.UK: Fire Safety (England) Regulations 2022, fire door guidance (updated 8 August 2025)
• Approved Document B: Fire safety
• Approved Document K: Protection from falling, collision and impact
• BS 8214 code of practice for fire doors (2026 edition, replacing the 2016 version), FPA report
• Regulatory Reform (Fire Safety) Order 2005
• DC Fire & Security: fire door inspection statistics

Updated October 2026 by Sebastian Grabowski, DC Fire & Security. We inspect and repair fire doors across Bedfordshire, Hertfordshire, London, the Thames Valley and the East Midlands. Our own figures: fire door inspection statistics 2026.