What are the Different Types of Intumescent Coatings?

Intumescent coatings, often referred to as intumescent paint, play a critical role in fire protection strategies across the globe. They offer a unique solution to protect structural elements from the devastating effects of fire. It can be part of a comprehensive passive fire protection system for buildings, which can, in turn, save lives. This article aims to provide a comprehensive understanding of intumescent paint, its working principle, its different types, and its role in a wider passive fire protection system.

Firstly, What is Intumescent Paint?


So, what is intumescent paint? Intumescent paint is a type of coating that reacts to heat by expanding and forming an insulating layer or carbon, also known as a char. This char is a poor conductor of heat, so it insulates and protects the underlying structure from the extreme heat of a fire. It’s often used to help protect load-bearing components of a building against fire damage and can also slow the spread of a fire.


Buildings greatly benefit from the application of intumescent paint around structural components as it slows temperature increases during a fire. If these components get too hot, then the entire structure could collapse quickly. So with intumescent paint, buildings are better protected from fires and are less likely to experience fast-spreading flames. This is also beneficial for any occupants during a fire outbreak, as it gives them more time to leave the building safely.


How Does Intumescent Paint Work?


Upon exposure to high temperatures typically resulting from a fire, the intumescent coating undergoes a chemical reaction causing it to expand, often up to 50 times its original thickness. This expansion results in the formation of a dense, foam-like char that effectively insulates and shields the structural material beneath from the intense heat, thereby reducing the rate at which the material will reach its critical failure temperature.


Different Types of Intumescent Coatings


While all intumescent paints work on the same principle of heat-triggered expansion, there are various types available, each with its unique benefits. From solvent-based paint to water-based alternatives, let’s take a look at the different types of intumescent coatings available:




Solvent-based intumescent coatings, also known as oil-based intumescent paints, are highly durable, weather-resistant and offer a smoother finish. They are typically used for exposed steel structures due to their resistance to moisture and superior aesthetic finish. Solvent-based coatings require specialised handling and ventilation during application due to the potentially hazardous fumes produced.




Epoxy-based intumescent coatings are two-component systems that offer the highest level of durability and fire protection – particularly against hydrocarbon fires. They are predominantly used in industrial settings, particularly for offshore oil and gas structures due to their resistance to harsh environmental conditions, including exposure to saltwater and chemicals.




Water-based intumescent coatings are the most environmentally friendly option. They produce fewer VOCs (volatile organic compounds) and are less hazardous during application. They are ideally suited for interior surfaces where ventilation may be limited, and a safer application process is required. However, they may not be as durable as the other types, especially in humid or exterior environments.


What Role Does Intumescent Paint Play in a Wider Passive Fire Protection System?


Intumescent paint forms a vital part of a passive fire protection system, which is a crucial element in the comprehensive approach to fire safety in buildings. But what is intumescent fireproofing? While active fire protection methods like sprinkler systems and fire extinguishers work to suppress or extinguish the fire, passive fire protection methods such as intumescent paint are designed to contain the fire and slow its spread, providing crucial extra time for occupants to escape and for fire services to respond.


Intumescent paint can protect structural elements like steel beams, columns, and concrete surfaces from collapsing under the heat of a fire. By preserving the structural integrity of a building, the risk of injury, loss of life, and property damage can be significantly reduced.


Expert Intumescent Coating Services at Ark Fire Protection


At Ark Fire Protection, we offer a comprehensive suite of intumescent coating services. Our team of certified professionals can guide you through the process, from selecting the right type of intumescent paint for your application to ensuring a thorough and safe application process. With our expertise, we can help you achieve optimal fire safety standards, ensuring your property is better protected from the devastating impact of fire.

Get in touch today to find out more about how we can help.

Get in touch to learn how we can help with your next fire protection project

Join over 1,000 UK businesses who have already had Fire Protection installed by Ark Fire Protection.

Get in touch

Recent Articles

Learn more about passive fire protection by reading other articles created by our experts.

fire warden

What is a Fire Warden?: A Guide

This guide aims to answer that question, outlining the day-to-day duties, monthly tasks, emergency responsibilities, legal requirements, and training processes involved.

Read more
Fire In An Old Building

How Long Does it Take for a Fire to Spread?

Fire can be a devastating force that can consume entire buildings in minutes if the conditions are right. Our latest article aims to provide insights into the speed at which fires can spread, the mechanisms behind fire spread, and ways to mitigate this potentially disastrous phenomenon.

Read more

New Partnership from Ark Fire Protection & Kings Secure Technologies!

We have partnered with Kings Secure Technologies (KST)! This collaboration allows KST, in conjunction with its group companies EFire for active fire & life safety systems and Quidvis for fire risk assessments (FRA) and fire door inspections, to enhance their service capability.

Read more