Fire-rated foam works by expanding once released from the tube, filling up the gap or penetration, and leaving no gaps for fire and smoke to pass through. It sets hard and then can be cut back to create a smooth, flush finish.
As it is non-combustible, it won’t catch fire and therefore won’t contribute to the spread of fire through a building.
When would you need fire-rated foam?
Fire-rated foam is often misused due to poor understanding of its suitability. It is important to note that it should only be used to fill small linear gaps, gaps between a door frame and wall, and small holes in fire walls.
It cannot be used to fill large voids or openings, and can only fill gaps up to 35mm wide. (Refer to the manufacturer's datasheet as application guidelines and test evidence may differ depending on brand).
Fire-rated foam is not suitable for use around pipe and cables as it doesn’t intumesce or expand in extreme heat so the services would burn away and leave a void and thus breach the fire compartment.
What's the difference between fire-rated foam and intumescent sealant?
A common mistake is for fire-rated foam to be used in situations where intumescent sealant is better suited.
While fire-rated foam expands on application, it sets hard and will not expand further and seal up a hole when a fire breaks out.
Intumescent sealant, on the other hand, does not expand when applied, and only swells up when a fire has broken out and it reaches a certain temperature. In this circumstance, the sealant will then expand and seal a hole to reinstate a wall or door’s fire containment properties.
Browse our selection of intumescent sealant and fire-rated mastics here.
Types of fire-rated foam
One of the best known fire-rated foams on the market is the Blue 60 Foam. It is used around door frames and can be used alongside door frame packers and comes with a wealth of test evidence, leaving you comfortable in knowing if it’s appropriate for your project.
Nullifire FF197 foam is also well known in the industry and can be used in fire door and concrete applications.
How We Can Help
If you need advice on the fire-rated foam or sealant you need for your project, get in touch with our expert team who will be happy to help you.
For more information on latest updates on regulations, specifications and fire stopping news visit our Advice Centre or give our Technical Helpline a call, for free, impartial advice.
