Two Approaches to Structural Steel Fireproofing
When it comes to fireproofing structural steel in New York City buildings, there are two primary passive fire protection approaches: spray-applied fireproofing (SFRM) and intumescent coatings. Both can achieve equivalent fire resistance ratings, but they are very different products suited to different applications.
Spray-Applied Fireproofing (SFRM)
Spray-applied fire resistive material is a thick, textured coating applied by spraying cementitious or mineral fiber material onto steel surfaces. It is the most cost-effective method for fireproofing large quantities of structural steel in concealed spaces — behind ceilings, in mechanical rooms, and in any area where the steel will not be visible in the finished building.
SFRM is fast to apply, economical, and provides reliable fire resistance ratings up to 3 hours or more. It is the standard choice for commercial office towers, hotels, hospitals, and any building where the structural steel is hidden from view.
Intumescent Fireproofing
Intumescent coatings are thin-film materials (typically 1–5mm thick) that react to heat by expanding dramatically, forming an insulating char layer that protects steel from reaching critical failure temperatures. Because they are thin and can be applied in any color, intumescent coatings provide a smooth, architectural finish — making them the only practical choice for architecturally exposed structural steel.
Choosing the Right System
The choice between SFRM and intumescent fireproofing comes down to three factors: aesthetics, cost, and environment. If your structural steel will be visible in the finished space — a modern lobby, open office, atrium, or industrial loft — intumescent fireproofing is the answer. If the steel will be hidden, SFRM is typically the more economical choice. For exterior applications or corrosive environments, epoxy intumescent systems may be required.
Working with Ali Firestop
Ali Firestop installs both spray-applied fireproofing and intumescent coatings across New York City. Our team can review your project plans and help you select the right system for your application, budget, and aesthetic requirements. Contact us to discuss your project.