Intumescent Paint Contractors
Intumescent fireproofing is a key asset for passive fire protection. By adding a protective layer to structural steel, intumescent paint extends the length of time a building can withstand high temperatures. This not only reduces damage to steel, it could make the difference between fully evacuating a building and putting the lives of occupants and firefighters at risk.
CLM Fireproofing specialises in the application of intumescent coatings for steel construction projects. With our in-depth technical knowledge, we can swiftly and effectively reinforce structural elements and surfaces, without compromising on their basic functionalities or aesthetic finishes. Our team is also able to apply intumescent coatings both onsite and offsite. This allows us to enact the strictest possible standards of quality control, so clients can be certain that their projects comply fully with building regulations.
As the UK’s leading specialists in passive fire protection and firestopping, our highly skilled operatives have worked on some of London’s standout commercial buildings, from The Shard to Battersea Power Station. Our guidance and technical advice assures clients that their projects are fully protected from structural fire damage. Consult our range of case studies to view our comprehensive range of fire protection projects.
With our years of hands-on experience, our installers can be brought on board at any point in the project lifecycle, helping to deliver fully compliant passive fire protection systems on time and within budget. As accredited members of the Association for Specialist Fire Protection (ASFP), we are committed to sharing knowledge, reducing any risks associated with non-compliance and empowering clients to maintain the highest building standards.
How does intumescent fireproofing work?
Under extreme conditions, steel will reach its ‘critical temperature’. The exact temperature can vary based on the building design. In Britain, it is commonly 550° but has been known to range between 350° – 750°. Once this point is reached the steel will begin to lose its nominal integrity and load-bearing capacity. Learn more about this in our guide to how fire affects structural steel.
In the event of a fire, the chemical properties of intumescent paints or sealants undergo an endothermic process. In other words, a chemical reaction causes the materials within the paints to expand when exposed to high temperatures. This offers additional protection for steel beams, columns and other structural elements, without affecting their mechanical properties or basic functionalities.
If a steel framework is coated with intumescent paint, the paint will expand into a carbonaceous char layer which solidifies once temperatures reach around 250°. This increases the steel’s fire resistance time whilst the building is evacuated. The exact performance of intumescent products can vary, offering 30, 60, 90 and 120 minutes of fire protection depending on the specific type of coating.
There are several ways to apply intumescent products as part of a structural fire protection strategy, the most common being spray application as a thin film coating. Intumescent paint can be applied to steel, timber and an array of composite building materials. Some varieties of intumescent paint can also be given a decorative finish. In this instance, we would engage with the manufacturer to ensure that all the coating finishes we use are compatible.
Intumescent coatings can be classified as either thin film or thick film. Thin film is the industry standard used to protect steel in buildings. In comparison, thick film intumescent coatings are mostly used to handle extreme temperatures in industrial environments, a common example being hydrocarbon fires.
How much does intumescent paint expand?
The rate of expansion for intumescent paint depends on its original thickness. Thin-film intumescent coatings will expand at a rate of 50:1, as a general rule of thumb. This means that a 1mm coating will reach an estimated density of 50mm in the event of a fire. Thick film coatings expand at an approximate rate of 5:1. It is worth mentioning that if a project intends to apply intumescent paint, then several aspects of the building should be designed to accommodate both the coating’s initial thickness and the rate of expansion.