fire resistant paint slowing down the burning process

Fire resistant paint: insulation against fire

Fire resistant coatings belong the group of coatings designed to increase fire safety. A substrate treated with fire resistant paint will be insulated against fire, because of the particular way that it responds to extreme heat. Fire resistant paint is also known as intumescent paint due to the fact that it swells in high temperatures. This insulating layer keeps the heat and flame from affecting the substrate.

When a fire resistant paint is exposed to fire a reaction is triggered and it swells, expanding to 15 or even 50 times its original volume. This forms a solid foam (char) which does not conduct heat, and which will erode as the fire continues. With more layers, the process can repeat. Fire resistant paints can add 30, 60, 90 or 120 minutes of extra protection against fire, and are given a rating depending on how long this protection lasts.

Fire resistant coatings are suitable for application on floors, walls and ceilings, decking, doors and bar tops.

Swell safety with fire resistant paint

Comparison of fire resistant paint treated vs untreated wood

Fire resistant paint treated wood vs bare wood

Fire resistant paint works by extending the time between fire breaking out and taking hold. When fire breaks out, fire resistant paint increases safety by:

  • keeping the structure secure for longer and holding off collapse
  • increasing the evacuation time
  • improving safety of the firefighters

Fire resistant coatings (not to be confused with fire retardant coatings) are an essential part of a proper fire protection coating system. They can either be applied alone, or as base coat for another coating which damps flames and protects the intumescent coating, delaying the burning even longer.

Fire resistant paint for all substrates

Benefits of fire resistant wood paint

One of the most common construction materials is wood, which is strong and long-lasting but very susceptible to fire. Fire resistant paints make wood and timber last even longer. Fire resistant (intumescent) paint for wood exists as clear coat, opaque paint (white and colour) as well as special fire resistant varnish. The benefits include:

  • Insulates wooden structures and surfaces from heat and flames
  • Increases surface durability

    Applying a fire resistant paint to metal

    Applying a fire resistant paint to metal

  • Protects from weathering and sun light
  • Applicable on both painted and untreated wooden surfaces

Benefits of fire resistant paint for metal

Steel does not burn like wood, but the extreme heat of a fire still damages it, and its strength and load bearing capacity is compromised. This leads to building collapse. Using an intumescent paint for steel will:

  • protect the steel structure from heat damage, keeping the building secure for longer
  • provide up to 120 minutes of fire protection
  • provide a decorative colour or finish, if desired

Fire resistant paint and safety standards

The fire resistant properties of coatings and other materials are standardised by measuring the time for which they provide a satisfactory level of fire resistant protection, for example 30 or 60 minutes. This means that a 30 minute fire rated coating surface effectively stops fire and prevents it from spreading for 30 minutes. There are two classes of fire resistance standard, class 1 and class 0. These regulations are included in BSI BS 476 Part 6.

Class 1 – The paint must not allow the spread of flame to be greater than 165mm in 10 minutes. This is a performance standard for fire resistant varnish and paint that can be applied to ceilings and walls.

Class 0 – Class 0 requirements are for high risk areas, corridors, staircases and escape routes. The requirements include class 1, but add an extra requirements known as the ‘Fire Propogation Index’ which measures how much the paint contributes to the fire. The coating must have a very low ability to catch fire and burn.

Get your fire resistant paint certified!

Whether you are applying the fire resistant coating yourself or having it done professionally, you should request a certification. Always request a proof of supply (for example receipt of the purchase). Most applicators also provide the certificate as a standard. A certificate of application of fire resistant coat is needed especially when discussing insurance policies or claiming insurance after actual damage.