When should thickness measurements be taken after applying SFRM?

Taking thickness measurements after SFRM (Spray-Applied Fire-Resistive Material) has stabilized is important because this timing ensures that the material has had enough time to settle and adhere properly to the substrate. Stabilization refers to the point at which the material has reached its initial set and can maintain its shape without significant deformation or shrinkage. This ensures that the measurements reflect the final thickness that contributes to the fire-resistance rating as specified by the manufacturer, accounting for any contraction that can occur during the curing process.

Measuring immediately after application would not provide an accurate reflection of the finished thickness, as the material could still be wet or in the process of settling. Waiting for full curing or drying may result in changes in thickness due to moisture loss or other factors. Therefore, stabilizing is the optimal point for making accurate measurements that inform compliance with safety and performance standards.