We recently completed cementitious fireproofing work inside a building in Yellowknife, Northwest Territories. The spray-applied material was installed across exposed structural steel beams and the underside of the steel deck.
The photos show the textured finish created as the fireproofing builds a protective layer around the structural members included in the project scope.
What Does Cementitious Fireproofing Do?
Cementitious fireproofing helps slow the rate at which protected structural steel heats up during a fire. Although steel does not burn, exposure to high temperatures can reduce its strength and affect its ability to carry the building load.
The fireproofing creates an insulating layer between the steel and the heat. This supports the fire-resistance design specified for the structural assembly.
The required material and application thickness are not the same for every project. They depend on factors such as:
- The specified fire-resistance rating
- The tested or listed assembly
- The size and shape of the steel member
- The structural member’s position
- The fireproofing product being used
- Project inspection requirements
For this reason, cementitious fireproofing must be applied according to the project drawings, specifications and product requirements.
Fireproofing Structural Steel and Metal Decking
The Yellowknife project involved coating several types of overhead structural surfaces. The fireproofing follows the profile of the steel beams and metal deck, creating coverage around edges, corners and changes in shape.
Overhead application requires control of the spray pattern and material build. Connections, narrow sections and areas where beams meet the deck need close attention because these locations can be more difficult to cover consistently.
The finished texture visible in the photos is typical of spray-applied cementitious fireproofing. Once dried, the material remains in place as part of the building’s passive fire-protection system.
Why Consistent Thickness Matters
The required fire resistance is based on the complete assembly, not simply the presence of fireproofing material. Thin sections, missed areas or damage caused by later construction work can affect the finished installation.
During application, attention is given to:
- Maintaining coverage across the specified surfaces
- Building the required material thickness
- Covering edges and difficult-to-reach areas
- Working around structural connections
- Avoiding exposed sections of steel
- Allowing the material to dry under suitable conditions
Completed fireproofing also needs to be protected as other trades continue working in the area. If material is removed or damaged while installing ducts, piping, wiring or other building systems, those sections may require repair before the structure is enclosed.
Planning Fireproofing Around the Construction Schedule
Cementitious fireproofing needs to be coordinated with the rest of the construction work. Structural steel should be ready for application, and welding or other work that could disturb the finished material should be completed beforehand whenever possible.
The work area also needs suitable access, ventilation and environmental conditions. Nearby surfaces, equipment and completed finishes may require protection during spraying.
Planning these details in advance helps keep the application moving and reduces the chance of having to return for avoidable repairs.
Cementitious Fireproofing for Commercial and Industrial Buildings
Spray-applied cementitious fireproofing may be specified for structural steel in commercial, industrial and institutional buildings. Common applications include columns, beams, joists and steel floor or roof decks.
Every project has its own structural design and fire-resistance requirements. We review the available drawings, specifications, member schedules and site conditions before establishing the application scope.
Learn more about our cementitious fireproofing services in Alberta.
Discuss Your Fireproofing Project
If your construction project specifies cementitious fireproofing for structural steel or metal decking, contact Northern Spray Solutions to discuss the drawings, required rating, application area and project schedule.
Call us at 1-780-963-4493 to discuss an upcoming commercial or industrial fireproofing project.