How to Protect Your Building with Passive Fire Protection

For those who don’t know or are new to fire protection…What is it?

Understanding how fire protection systems work is important and there are numerous methods, but they all have the same goal: to detect a fire and protect the building, its occupants, and the emergency services.

There are two types of fire protection, active fire protection and passive fire protection. 

Active Fire Protection includes common systems such as fire alarms and Sprinklers. Sprinkler systems turn on when smoke alerts the detector that a fire has started, followed by a sequence of water which is sprayed upon the area of concern, neutralizing the fire from spreading further. 

Passive fire protection encompasses systems such as Fire Doors, Fire Escapes, Fire Stopping Products, and Intumescent Coatings which are incorporated into a building design during the early stages of construction. These passive fire protection systems use materials which give compartmentation, reducing the ability and speed of fire spread, stopping structural collapse, and providing more time for the occupants of the building to escape safely.

Let’s dive deeper into Intumescent Coatings…

What is an Intumescent Coating?

When a fire breaks out, passive fire systems such as intumescent coatings aim to prevent structural failure and collapse of the building so that there is more time for occupants to evacuate and for emergency services to respond to the fire. 

An intumescent coating is a specially formulated protective coatings system, which is applied to the steel structure of a building during early construction either in the factory or onsite.  Intumescent coatings are applied by spray equipment and can be water-based or solvent based acrylics, epoxy, or unique hybrid technologies i.e., Nullifire SC902.

In the event of a fire, intumescent coatings help to reduce structural failure and maintain compartmentation, limiting the spread of fire, reducing the number of areas within a building being damaged.

How does an Intumescent Coating provide protection against fire?

Intumescent coatings are designed to protect structural steel from reaching a critical structural failure temperature (this typically tends to occur around 500ºC), where steel will begin to lose its strength and cause potential building collapse. Intumescent coatings, once they are exposed to temperatures of around ~200°C[1], the coating starts to react and expands to provide an insulating barrier forming a stable, carbonaceous char which reduces the rate of heat conducted to the steel.   This carbonaceous char must have the ability to remain in-situ during any movement of the steel, such as expansion or deflection, until the required protection criteria is achieved.


How do I know which Intumescent Coating is right for my building?

There are many different intumescent coating technologies, which have various application characteristic and performance benefits or restrictions.

Below are four common generic types of intumescent coating systems;

1. Water-based Acrylic Intumescent

Water-based acrylic intumescent coatings are generally the lowest cost type of these materials to purchase per litre but are an expensive solution at higher fire ratings to apply as they require multiple coats to achieve the overall required thickness. These coatings cure by water evaporation and should only be used in an internal dry atmosphere due to the acrylic resin system not being tolerant to moisture.

2. Solvent-based Acrylic Intumescent

Solvent-based acrylic intumescent coatings are a slightly higher cost to water based acrylic intumescent systems and are still high cost to apply due to multiple coat applications. They are slightly more tolerant to atmospheric exposure than water based acrylic intumescent but again due to the acrylic resin should be used in internal atmospheres. 

3. Epoxy-based Intumescent

Epoxy-based intumescent coatings are derived from the oil and gas industry and are capable of withstanding very aggressive environmental conditions. The technology has been transferred into the commercial project space but is a very expensive solution and complex to apply with plural equipment being required.

4. Hybrid Intumescent

This is a unique patented technology from Nullifire which is cost effective, as it can be applied in a single coat depending upon the visual requirements. It can easily be applied in either the factory or onsite using simple electric airless equipment. This technology works for both the construction and final environment due to its quick cure characterises along with being very tolerant on the atmospheric application requirements.

When considering the right intumescent protection for your structure, you need to consider a range of key factors including the fire rating, steel size selection, the limiting steel temperature, where the product will be applied (factory or site) the construction and final environment.

Government Standards, Industry Standards and Australian Standards

In Australia, fire safety regulations and standards are implemented to ensure that buildings and occupants within them are protected in the event of a fire, via the National Construction Code.

When choosing a structural steel fire protection system like intumescent coatings, you should ensure products have been tested and assessed to meet the requirements of AS1530.4- 2014 and AS4100-1998, which is a requirement from the National Construction Code.

Whether you are looking to learn more about the Nullifire’s range of products, source materials or are looking for technical assistance, we are here to help.

Passive fire protection is highly complex but critical to ensure building structures and their occupants are safe and given the maximum time to move to safety in the event of a fire. At Tremco CPG Australia, we understand the need to have confidence in fire protection. Our Nullifire products and global brand reputation provide the reassurance that our products will deliver the ultimate in fire protection for your facility.

Talk to Our Fire Protection Specialist Today:

Chris Partington
Passive Fire Protection Specialist
Nullifire – Part of Tremco CPG Australia Pty Ltd
M: 0498 002 633


[1] Based on Nullifire Intumescent Coatings