What is the minimum slope percentage for flashing?

What is the minimum slope percentage for flashing?

• A. 6%
• B. 4%
• C. 8%
• D. 5%

Answer: (A)

Water needs a clear path to drain away from joints and penetrations, and flashing must have a positive slope to carry moisture off rather than letting it pool behind it. The minimum slope often recommended for flashing in residential construction is six percent, which means about 0.72 inches of rise per foot of run. This gradient helps water shed effectively and reduces the chance of leaks at roof penetrations or transitions. Slopes lower than that, like four or five percent, can allow water to linger behind the flashing, increasing the risk of intrusion. A steeper slope, such as eight percent, will still work but isn’t necessary to meet the minimum requirement.

Water needs a clear path to drain away from joints and penetrations, and flashing must have a positive slope to carry moisture off rather than letting it pool behind it. The minimum slope often recommended for flashing in residential construction is six percent, which means about 0.72 inches of rise per foot of run. This gradient helps water shed effectively and reduces the chance of leaks at roof penetrations or transitions. Slopes lower than that, like four or five percent, can allow water to linger behind the flashing, increasing the risk of intrusion. A steeper slope, such as eight percent, will still work but isn’t necessary to meet the minimum requirement.