On steep roofs, what is the minimum drip edge extension back over the roof deck in inches?

On steep roofs, what is the minimum drip edge extension back over the roof deck in inches?

• A. 1
• B. 4
• C. 3
• D. 2

Answer: (C)

Water management at the roof edge requires a minimum extension of three inches of drip edge back over the roof deck. This length ensures water is directed into the gutter and prevents it from wicking behind the edge into the roof decking and fascia. It also provides proper overlap with the shingles and underlayment, helping protect the eave from leaks. Four inches would meet the requirement but isn’t the minimum, while two or one inch wouldn’t provide enough protection, making three inches the correct minimum.

Water management at the roof edge requires a minimum extension of three inches of drip edge back over the roof deck. This length ensures water is directed into the gutter and prevents it from wicking behind the edge into the roof decking and fascia. It also provides proper overlap with the shingles and underlayment, helping protect the eave from leaks. Four inches would meet the requirement but isn’t the minimum, while two or one inch wouldn’t provide enough protection, making three inches the correct minimum.