Fire Resistance

Concrete’s resistance to fire improves the safety of occupants, fire fighters and neighbours during fire events, and minimises damage, so buildings can return to use quickly, boosting community resilience.

During a fire, temperatures can reach more than 1000°C very quickly with thermal gradients of tens of degrees Celsius per minute. In these conditions, construction materials may partially or totally lose their mechanical properties, leading to the collapse of structural elements. In addition to immediate safety concerns, such a complete building collapse brings longer-term social and economic disruption.

As a result, fire resistance (a specific property of structural elements) and fire resilience (the capacity of a building to maintain function in the aftermath of a fire) are interlinked. If appropriately designed, concrete is both resistant to fire and therefore able to provide fire resilience to the built environment. Its advantages include:

  • Resistance to fire without burning, melting, or producing toxic gases.
  • Ability to act as a fire barrier, reducing the spread of fire to neighbouring spaces or buildings.
  • Ability to act as an insulator, reducing transfer of heat to adjacent spaces.
  • Maintaining integrity during a fire, including during extinction, without developing large deformations, ensuring compartmentation of the fire is maintained and reducing the risk of structural collapse.
  • No emission of CO2 or substances dangerous to people or the environment when affected by fire.
  • No need for additional fire protection measures and materials.
  • No risk that building refurbishment will compromise fire protection measures, as these measures not needed, unlike for other structural materials.
  • Reduces risk posed by faulty fire safety measures (fire doors, alarms, ventilation strategies, sprinklers) because concrete is inherently fire resistant.

Beyond these practical benefits, it is becoming increasingly common to recognise resilient structures as a key component of economic, social, and environmental sustainability. By helping to limit the extent of damage caused by fire, concrete buildings ensure communities recover more quickly and lower the need for demolition and reconstruction, reducing the economic and environmental cost of fire events.

Header photo by Paul Mocan on Unsplash