What is Intumescent Hardware Protection?

WHAT is Intumescent Hardware Protection?

Intumescent Hardware Protection is fire rated material used with fire door ironmongery.

HOW is Intumescent Protection used with Fire Door ironmongery?

This thin (0.5mm - 2.0mm) material is fitted behind or around fire door hinges, locks, latches and bolts etc.. to form a barrier that helps to fill the air gaps (created when you cut into a door or frame to fit the ironmongery).

The material is designed to expand, in the event of a fire, to fill the small air gaps (which help stop the fire coming into the door) and help the ironmongery stay in place.

Does my fire door ironmongery REQUIRE Intumescent Protection?

It is estimated that over 99% of ALL fire rated door hardware MUST be fitted with the correct material (type and thickness) to validate the ironmongery fire certificate.

What happens if I DON’T fit Intumescent when it is REQUIRED?

If you DON’T fit Intumescent Hardware Protection, when your fire rated ironmongery requires it, this can result in:

  • Your fire door FAILING a fire inspection
  • Your fire door FAILING in the event of a fire
  • £1000’s in legal fees, fines & the cost of repair work

Intumescent Protection Material: TECHNICAL Information

There are two main types of material.

  • Graphite based (dark grey/black in colour)
  • Mono Ammonium Phosphate or MAP (white in colour, sometimes called by the Brand name 'Interdens')

There are 4 main thickness of material (important for specification)

  • 0.5mm - can be both graphite and MAP
  • 0.8mm - mostly found in graphite only
  • 1.0mm - can be found in both graphite and MAP (most commonly used in FD30 doors)
  • 2.0mm - can be found in both graphite and MAP (most commonly used in FD60 doors)

What is the difference between GRAPHITE and MAP intumescent material?

Both graphite and MAP material perform the same function ie to fill the gaps created when you cut into a fire door or frame (to fit the ironmongery). In the event of a fire they EXPAND up to 20 times their original size to seal the gaps in the door and frame.

Where you have a CHOICE, the differences are.

  • Graphite material is smooth, non-fibrous and flexible (also easy to un-stick and re-apply)
  • MAP material is fibrous to touch and non-flexible (it normally snaps if you try and un-stick it)


It is important to make sure you buy the correct material and thickness to suit your fire door.

Click here to read our ’Intumescent Protection: Specification & Buying Guide’

Further Information & Support

Fire Essentials Ltd is part of the 'Catch The Killer' awareness campaign and we work with companies and installers EVERY DAY to help them get the right product for their fire doors.

We specialise in Intumescent Protection and work closely with teams that have developed and manufacture these products in the UK.

For further assistance please contact us:

Email our central team at info@FireEssentials.co.uk
Call our helpline on 01305 457703
Complete the online form and one of our team will get back to you (within 2 working hours)

'It is our job, to make YOUR JOB easier'