What is the minimum slope required for a built-up roof?

What is the minimum slope required for a built-up roof?

• A. 1/8:12
• B. 1/4:12
• C. 1/2:12
• D. 3/4:12

Answer: (B)

The minimum slope required for a built-up roof is 1/4:12. This guideline is established to ensure proper drainage and to prevent water accumulation on the roof surface, which can lead to leaks and structural damage over time. A slope of 1/4:12 means that for every 12 horizontal inches, the roof rises a minimum of 1/4 inch. This slope is generally accepted as a standard to effectively channel water off the roof and discourage ponding. If the slope were lower, such as 1/8:12, it may not provide sufficient drainage, increasing the risk of water pooling. Slopes greater than 1/4:12, while also effective, are not required for built-up roofs and may be excessive for certain design specifications, thus it is essential to adhere to the minimum guidelines provided by the North Carolina Residential Code.

The minimum slope required for a built-up roof is 1/4:12. This guideline is established to ensure proper drainage and to prevent water accumulation on the roof surface, which can lead to leaks and structural damage over time. A slope of 1/4:12 means that for every 12 horizontal inches, the roof rises a minimum of 1/4 inch. This slope is generally accepted as a standard to effectively channel water off the roof and discourage ponding.

If the slope were lower, such as 1/8:12, it may not provide sufficient drainage, increasing the risk of water pooling. Slopes greater than 1/4:12, while also effective, are not required for built-up roofs and may be excessive for certain design specifications, thus it is essential to adhere to the minimum guidelines provided by the North Carolina Residential Code.