In modern Saudi construction, structural steel is the backbone of most high-rise towers, malls, and large-span structures. But steel has a critical weakness: it loses over 50% of its strength at approximately 550°C. In a fire, an unprotected steel frame can collapse in as little as 15-20 minutes. Fire-Boards are a primary solution to this problem, providing a clean, durable, and certified method of “structural fire protection.”

This process, known as encasement, involves boxing in steel columns and beams with fire-rated boards. This insulates the steel from the fire’s heat, delaying the time it takes to reach its critical failure temperature and ensuring the building remains standing for the required 1, 2, or 3 hours.

Why Unprotected Steel is a Major Risk

Steel does not burn, but it does lose its load-bearing capacity when heated. The Saudi Building Code (SBC) mandates that the structural frame of a building must have the same fire-resistance rating as the floors and walls it supports. For a high-rise, this can be 2, 3, or even 4 hours. An unprotected steel frame offers almost no fire resistance, making structural fire protection a life-safety-critical requirement.

How Fire-Board Encasement Works

As a key passive fire protection service, encasement is a precise, dry-fix process:

1. Board Selection: A high-performance Fire-Board is selected (often a rigid calcium silicate or mineral wool board).
2. Framing (if needed): A light-gauge steel frame is built around the column or beam.
3. Board Fixing: The boards are cut and fixed to the framing (or directly to each other) using specialized fixings (screws, staples, or clips).
4. Multiple Layers: For higher ratings (e.g., 2 or 3 hours), multiple layers of board are required, with all joints staggered to prevent heat penetration.

Boards vs. Sprays: Which is Better?

Fire-resistive spray (Intumescent paint or cementitious spray) is another common solution. However, fire-boards are often the superior choice, especially in KSA’s high-spec buildings.

Critical Factor: The “Hp/A” Ratio

The thickness of the fire-board required is not “one size fits all.” It is a precise calculation based on the steel section’s “Hp/A” ratio—its heated perimeter (Hp) divided by its cross-sectional area (A). A thin, lightweight steel section (high Hp/A) will heat up much faster than a thick, heavy one (low Hp/A) and will therefore require a *thicker* fire-board to achieve the same 1-hour or 2-hour rating.

As our past projects show, our technical team performs these calculations for every steel member to ensure the correct, most efficient board thickness is specified and installed.

“Protecting the steel is protecting the building itself. Fire-board encasement is the definitive, robust, and aesthetically superior method for ensuring structural integrity in a fire.”

Conclusion: A Clean, Certified, and Critical Solution

Fire-Board encasement is a critical life-safety system, not just a cosmetic finish. It is the most reliable “dry” method for protecting structural steel, offering a sharp, durable finish that cementitious sprays cannot. Partnering with a certified specialist ensures that all Hp/A calculations are correct and the installation is fully compliant with the SBC and the manufacturer’s tested system.

Need to protect the structural steel on your KSA project?

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