All of the contractors I have spoken to, both painting and fireproofing, have expressed less than happy results with their first application of intumescent fireproofing. Some have decided to avoid it in the future. I understand that many architects have unhappy stories to tell as well.
I suspect that all professions involved, from manufacturer to architect, have each had a contributing part to this unhappiness.
The basic problem is that traditional passive fireproofing (SFRM – Spray-Applied Fire
Resistive Materials) and intumescent fireproofing (IFRM – Intumescent Fire Resistive Materials) are totally different materials with the exception that they are both fire-resistant* coatings and therefore Life-Safety products. The cost, the aesthetic results, and even the application tools are quite different for intumescent products than they are for conventional SFRM’s. These factors more closely resemble those of commercial painting. Architects and contractors have picked up on the “intumescent coating” and “thin film” key words in IFRM product descriptions, and incorrectly translated that into “intumescent paint” and assumed it was easily done by a painting contractor.
The successful application of intumescent coatings belongs neither to SFRM applicators nor to painting applicators. Neither painters nor fireproofers, as part of their respective trades, already have the qualifications needed to successfully apply intumescent fireproofing. Each will have to acquire some of the abilities of the other.
An SFRM applicator looks at an intumescent coating he has done and thinks “This is ten times thinner and looks ten times smoother than I usually apply, this is great”, and the painter thinks “this looks good, who cares how thick it is,”, but his thicknesses don’t pass inspection. (Or perhaps: “I applied it the best I could, and it is dripping down to the floor.”) The architect looks and thinks “This doesn’t look like paint on steel, and that is what I paid a premium for.”
Architects and owners have relied on contractors to bid and deliver products that adhere to the building codes and their aesthetic expectations. This is a general industry standard expectation, as it should be. But it has one foot in fireproofing and one foot in painting.
Perhaps a better description of some IFRM’s would be something like: “Fireproofing that is much thinner than conventional SFRM fireproofing and can be applied by equipment that painting contractors use. It can be made to conform to the shape of the steel, but the degree of that conformity, and also the surface smoothness depend on the knowledge and abilities of the applicator.”
*Fire-retardant coatings are something very different as they are only tested to ASTM E-84 and NOT ASTM E-119/UL 213