Fireproofing Explained: Intumescent vs Thick-Film Coatings

1 hour or 2.5 hours of fire rating? How coating type, thickness and cost relate — clearly.

Fireproofing steel means slowing its temperature rise: above 500°C steel loses over half its strength. Coating selection follows the required fire resistance:

Intumescent (thin-film): about 2mm at room temperature, foaming into an insulating char in fire. Attractive and light — suited to exposed steel in showrooms and offices; typically up to 1.5 hours of rating, at higher cost.

Thick-film (non-intumescent): 8–40mm of insulating material itself, reaching 2.5–3 hours, economical but rough-looking — usual for concealed plant areas or above suspended ceilings.

Note for exports: fire codes differ widely by destination (EN 13381, UL listings, etc.) — confirm coating certification at design stage, not when inspection paperwork is missing.