North Carolina Building Contractor License Practice Exam

What is the standard measurement for notching at the ends of rafters?

1. 45 degrees

2. 30 degrees

3. 60 degrees

4. 15 degrees

The correct answer is: 45 degrees

The standard measurement for notching at the ends of rafters is commonly accepted to be 45 degrees. This angle allows for an effective load distribution and minimizes the risk of structural weakness in the rafter. Notching at a 45-degree angle helps to create a more secure connection between the rafter and the supporting members, such as the ridge board or the plate, ensuring better performance under various loads. Notching rafters correctly is crucial; improper angles could lead to stress concentrations that could compromise the integrity of the roof system. A 45-degree notch offers a balance between providing enough of a bearing surface for connection while also reducing the amount of wood removed, thus maintaining overall rafter strength.