Intumescent Fireproofing in New York City
Intumescent fireproofing is a thin-film, paint-like coating applied to structural steel that provides fire resistance through a chemical reaction. When exposed to high heat from a fire, the intumescent coating expands (or "intumesces") to many times its original thickness, forming an insulating char layer that protects the steel from reaching critical failure temperatures.
Unlike traditional spray-applied fireproofing, intumescent coatings provide a smooth, attractive finish — making them the preferred choice for architecturally exposed structural steel in modern commercial buildings, atriums, lobbies, and open industrial spaces throughout New York City.
Why Choose Intumescent Fireproofing?
- Aesthetic Appeal — Provides a clean, architectural finish compatible with exposed steel design intent
- Space Efficiency — Thin coating (typically 1–5mm DFT) adds minimal bulk compared to SFRM or board systems
- Durability — Suitable for interior and exterior applications, including corrosive environments
- Flexibility — Available in virtually any color to match architectural specifications
- Code Compliant — UL-listed systems provide 1-hour, 2-hour, and 3-hour fire ratings
Our Intumescent Fireproofing Services
Ali Firestop provides complete intumescent fireproofing installation for new construction and renovation projects across New York City. Our team is trained and certified in the application of leading intumescent coating systems.
Products We Apply
We work with the industry's leading intumescent fireproofing products to deliver the right system for every application:
- Nullifire — Water-based and solvent-based systems for interior and exterior applications
- Sherwin-Williams FIRETEX — High-performance intumescent coatings for structural steel
- Jotachar — Epoxy intumescent systems for industrial and offshore environments
- Isolatek CAFCO — Intumescent systems for architectural and structural applications
Applications
- Architecturally exposed structural steel (AESS)
- Steel columns, beams, and trusses
- Steel stairs and mezzanines
- Transfer structures and long-span beams
- Mechanical penthouses and roof structures
- Industrial facilities and warehouses
- Parking structures with exposed steel
Our Application Process
Surface Preparation
Proper surface preparation is critical to intumescent coating performance. We prepare steel surfaces to the blast or prime coat specification required by the coating system and the project engineer.
Primer Application
An approved primer coat is applied to provide adhesion and corrosion protection beneath the intumescent topcoat.
Intumescent Coat Application
The intumescent coating is applied in multiple coats to achieve the specified dry film thickness (DFT) required for the target fire rating. We use airless spray application for efficiency and consistency.
Topcoat Sealer
A topcoat sealer is applied over the intumescent layer to provide protection against moisture, abrasion, and UV exposure, and to achieve the specified finish color.
DFT Testing & Documentation
After application, we conduct dry film thickness testing using calibrated magnetic gauges and provide a complete test report documenting compliance with the specified fire rating.
Fire Rating Capabilities
Depending on the section factor of the steel and the intumescent system selected, Ali Firestop can achieve:
- 1-hour fire rating
- 1.5-hour fire rating
- 2-hour fire rating
- 3-hour fire rating
All ratings are based on UL-listed designs and comply with NYC Building Code requirements.