What is the minimum roof slope required for modified bitumen roofing?

The minimum roof slope required for modified bitumen roofing is 1/4 inch in 12. This slope is important because it helps ensure proper drainage of water from the roof surface, reducing the risk of ponding, which can lead to leaks and decay over time. A slope of 1/4 inch in 12 means that for every 12 inches of horizontal distance, the roof rises at least 1/4 inch, which is sufficient to facilitate drainage while still providing a flat appearance, common in modified bitumen roofing installations. This specification aligns with industry standards and best practices designed to enhance the longevity and performance of the roofing system. Other options represent slopes that may not effectively support proper drainage for modified bitumen roofing, potentially leading to future complications.