National Occupational Competency Testing Institute (NOCTI) Carpentry Practice Exam

What does Rim Board do in a construction project?

1. Provides lateral stability to the walls

2. Acts as the edge for floor joists

3. Serves as a decorative trim piece

4. Supports the roof structure

The correct answer is: Acts as the edge for floor joists

The rim board plays a crucial role in the structural integrity of a construction project by acting as the edge for floor joists. This component bridges the ends of the joists, providing a solid perimeter for the floor framing. It helps to distribute loads evenly across the floor system and enhances the overall stability of the structure. Additionally, the rim board offers support for the floor sheathing, creating a continuous surface that contributes to the flooring's strength. By serving as an attachment point for the joists, the rim board also helps prevent lateral movement and twisting of the joists, which can be critical for maintaining level floors. Its placement is integral to ensuring that the floor framing is effective, reliable, and capable of accommodating structural loads. The other options do not accurately define the primary function of the rim board, as it is not designed for decorative purposes, lateral wall stability, or direct roof support. Each of these functions belongs to other elements of the framing system, underscoring the unique and important role that the rim board fulfills in construction.