North Carolina Building Contractor License Practice Exam

What is the minimum requirement for bolt diameter when anchoring to masonry walls?

1. 1/4 inch

2. 3/8 inch

3. 1/2 inch

4. 5/8 inch

The correct answer is: 1/2 inch

The minimum requirement for bolt diameter when anchoring to masonry walls is specified to ensure that the bolt can provide adequate strength and support for the structure being anchored. A bolt diameter of 1/2 inch is commonly recommended because it strikes a balance between the strength needed for most applications and the ease of installation. Masonry, which can include materials such as concrete, brick, or stone, requires a substantial bolt size to ensure that it can withstand various forces, including tension, shear, and shear-compression that may act upon it. A 1/2 inch bolt provides enough shear resistance and load-bearing capacity to effectively hold fixtures or other elements securely in place. Using a smaller diameter bolt, such as 1/4 inch or 3/8 inch, might not provide sufficient strength, especially in applications with heavy loads or significant stress. Conversely, a bolt larger than 1/2 inch, while potentially stronger, may not be necessary for many standard applications and could complicate installation and increase costs without providing proportional benefits. Therefore, a 1/2 inch bolt is recognized as a suitable minimum size for effective anchorage to masonry walls.