Design & Tools

Fire Protection

Providing fire protection to structural members allows for larger non-compartmentalized spaces, whether by adding gypsum sheathing or by providing a sacrificial char layer to structural elements. Table 601 of the 2012 IBC indicates the resistance required for each structural element (i.e., roof, floor, exterior walls, etc.) for a given construction type and specified level of protection—A or B. Fire resistance is measured in hours and ranges from 0 to three hours of protection.

Type IV (heavy timber) construction is considered self-protected. The prescriptive requirements for Type IV construction include sizing to accommodate charring protection in the case of a fire.

For wood members and assemblies, there are five ways to establish fire resistance as outlined in Sections 703.2 and 703.3 of the 2012 IBC. The three most common are as follows:

  1. Sourcing tested assemblies. Although most people think of United Laboratories (UL), there are other sources of assemblies, such as the American Wood Council.
  2. Specifying an assembly that matches the descriptions in the deemed-to-comply tables found in 2012 IBC Section 721.
  3. Calculating the fire resistance per Section 722 of the 2012 IBC. For more information: