For floor framing in Type IV construction, beams must have a minimum depth of which dimension?

In Type IV construction, which is commonly known as heavy timber construction, there are specific requirements for the sizing of floor framing components. The requirement for beams to have a minimum depth of 12 inches is rooted in the building code's aim to ensure structural integrity and fire resistance.

The dimension of 12 inches is significant because it allows for adequate load-bearing capacity while also providing enough thickness for effective fire resistance. This depth helps to prevent the rapid propagation of fire through the structural elements and provides a greater margin of safety by ensuring that the beams can withstand both vertical and lateral loads effectively.

Choosing a smaller dimension, such as 6 inches or 10 inches, could compromise the structural support and fire safety performance established by the building regulations for Type IV construction. Therefore, the requirement for a minimum beam depth of 12 inches is crucial for ensuring that the structure meets safety and performance standards.