North Carolina Building Contractor License Practice Exam

What is the minimum width for valley lining made of metal?

1. 18 inches

2. 30 inches

3. 24 inches

4. 12 inches

The correct answer is: 24 inches

The minimum width for valley lining made of metal is established to ensure proper water drainage and protection of the roofing structure. In this case, a width of 24 inches is required to effectively manage water flow in the valleys, which are critical areas on a roof where two planes meet. This dimension allows enough surface area to direct water away from the seams and into the gutters, minimizing the risk of leaks and water damage. Additionally, the 24-inch width accommodates various installation methods and materials, which helps ensure that the metal lining can be effectively secured while maintaining structural integrity. Structures using narrower widths may be prone to issues such as improper drainage or increased wear due to environmental exposure. The other options do not meet the established standard width for valleys, which could lead to complications in water management and roofing durability.