Reaction to fire and Fire resistance

Date Published

21 September 2022

Document Type





Reaction to fire classifications are completely different to fire resistance ratings yet the two terms are often misunderstood and taken to mean the same thing. This is not the case. This publication aims to set out the important differences. Understanding fire performance terminology starts with understanding the stages in the development of a fire.

Key Information

The key differences between reaction to fire and resistance to fire.

Reaction to fire is the measurement of how a material will contribute to the fire development and spread, particularly in the very early stages of a fire when evacuation is crucial.

Fire resistance is the measurement of the ability of a building/construction element to resist, and ideally prevent, the passage of fire from one distinct area/building compartment to another.

Case studies

The Stonebridge Hillside Hub is a key scheme in the continuing regeneration of the Stonebridge Estate in West London.

There is nothing in the building regulations that prohibits high-rise timber buildings, although the practical limit (and current
code limitation) for stud wall timber frame is seven storeys. The Stadthaus (German for townhouse) is – with eight floors of timber structure – the tallest habitable timber building in the world.