Intumescent Coatings – explained

Often confused as ‘fire rated paint’. The Intumescent coating acts very differently to other fire rated systems in such that it isn’t designed to stop the spread of fire. In fact Intumescent Coatings are designed to limit the heat impact upon the structural steel. Therefore Intumescent coatings are more of a ‘Structural’ building element than they are ‘spread of fire’.

A couple of key early pointers to consider with regard to Intumescent coatings:

1. Intumescent Coatings are designed to limit the heat upon the steel members – therefore a piece of steel may get hot & heat up but not allow the spread of flame through. The heat upon the steel will soften the steel & reduce its structural capacity. Therefore we are wanting to limit the heat upon the steel to ensure the structural integrity of the steel member stays within design parameters from a Structural aspect.
2. Intumescent coatings work by expanding under heat & insulating the steel from the heat – therefore if the coating can’t expand it won’t be able to insulate the steel member, meaning timber blocking & linings can’t be applied hard over intumescent paint. Think of it like a life jacket on a plane – if the life jacket can’t inflate it is no good to you.
3. Application climatic conditions will impact on the compliance of the intumescent paint – very strict application criteria should be followed and QA records kept
4. Quality Assurance at all stages of Intumescent Coatings is critical. Including design, application, completion. No records means there is risk that the design or application is wrong and compliance could be jeopardized.
5. Design phase – if Intumescent coatings aren’t considered in the design phase then it is too late to get it right. Decisions will already have been made that will jeopardize your projects compliance and result in non-compliances and cost headaches.