North Carolina Building Contractor License Practice Exam

Joist bridging is required if the depth to thickness ratio exceeds what value?

1. 20 inches

2. 36 inches

3. 48 inches

4. 60 inches

The correct answer is: 48 inches

Joist bridging is a critical structural component used to enhance the stability and load distribution of floor and roof framing systems. When the depth to thickness ratio of a joist exceeds a certain value, the structural integrity of the joist can be compromised due to potential lateral-torsional buckling or deflection. In this context, the requirement for bridging is set at a depth to thickness ratio that exceeds 48 inches. This ratio serves as a guideline ensuring that the joist retains its strength against lateral movements and maintains adequate performance under load conditions. If the depth to thickness ratio is greater than 48 inches, additional bridging is necessary to provide the necessary lateral support. Understanding this ratio and the requirement for bridging is crucial for ensuring that framing systems are designed to withstand the stresses imposed on them, ultimately contributing to the overall safety and durability of the structure.