What is the surface texture characteristic of spray-applied fire-resistive materials (SFRM)?

The surface texture characteristic of spray-applied fire-resistive materials (SFRM) is typically rough, which can be attributed to the nature of the application process. When SFRM is sprayed onto surfaces, it creates a fibrous and uneven texture that serves several essential purposes.

The roughness of the surface enhances bonding with substrates and allows the material to effectively adhere, ensuring that it can fulfill its fireproofing role. Additionally, this texture contributes to the thermal performance of the material, as the uneven surface can help in creating air pockets that improve the insulation properties.

In contrast, a smooth surface, like polished concrete, or a flat and even surface does not provide the same level of fire resistance or insulation capabilities. A textured and shiny finish would typically indicate a different type of application or material not suited for fireproofing purposes. Therefore, the rough texture is a defining characteristic of SFRM, aligning perfectly with its intended purpose and application process.