What is the maximum column web depth allowed if a primer is used beneath SFRM?

The maximum column web depth allowed when using a primer beneath Spray-Applied Fire-Resistive Material (SFRM) is indeed 16 inches. This specification is important because the application of primer can affect the bonding and overall performance of the fireproofing material. SFRM needs to be applied properly to ensure that it performs effectively in the event of a fire, providing the necessary insulation and protection for structural elements.

When primers are utilized, they can add a layer to the substrate, potentially influencing how well the SFRM adheres. The 16-inch limit on web depth is established as a practical guideline to ensure optimal bonding and coverage of the fireproofing material. Beyond this depth, the effectiveness of the fire-resistive system may be compromised, which is why a specific maximum depth is indicated in the guidelines.

It’s critical to adhere to these limitations during construction and fireproofing application to maintain compliance with safety standards and ensure the structural integrity and fire resistance of the building.