What is the minimum diameter of bolts used to anchor a roof structure to a masonry wall?

What is the minimum diameter of bolts used to anchor a roof structure to a masonry wall?

• A. 3/4 inch
• B. 3/8 inch
• C. 1/2 inch
• D. 1 inch

Answer: (C)

When attaching a roof structure to a masonry wall, the fasteners must be large enough to develop sufficient uplift resistance in masonry. The minimum diameter that meets typical maintenance and code requirements for these anchor bolts is one-half inch. This size provides enough thread engagement and pullout resistance to handle wind loads without risking failure, while smaller diameters would not reliably meet the required strength. Larger diameters, such as three-quarters of an inch or one inch, aren’t necessary as a minimum—they’re used only in heavier-duty designs or special conditions. Always follow the local code and the engineer’s specifications, but one-half inch is the standard minimum for this application.

When attaching a roof structure to a masonry wall, the fasteners must be large enough to develop sufficient uplift resistance in masonry. The minimum diameter that meets typical maintenance and code requirements for these anchor bolts is one-half inch. This size provides enough thread engagement and pullout resistance to handle wind loads without risking failure, while smaller diameters would not reliably meet the required strength. Larger diameters, such as three-quarters of an inch or one inch, aren’t necessary as a minimum—they’re used only in heavier-duty designs or special conditions. Always follow the local code and the engineer’s specifications, but one-half inch is the standard minimum for this application.