What is the minimum underlayment for asbestos-cement shingles?

What is the minimum underlayment for asbestos-cement shingles?

• A. 15 lb
• B. 30 lb
• C. 10 lb
• D. 20 lb

Answer: (A)

The test is asking about the minimum weight of underlayment to use under asbestos-cement shingles. Underlayment serves as a secondary moisture barrier and helps protect the deck and provide a smooth surface for the shingles to seat against. For asbestos-cement shingles, the standard minimum is 15 pounds per square of asphalt-saturated felt. This weight strikes a balance between adequate moisture protection and practicality. Heavier underlayments, like 30 pounds, are used in more demanding conditions or with other roof types, while lighter or nonstandard weights aren’t required as the minimum for this roofing.

The test is asking about the minimum weight of underlayment to use under asbestos-cement shingles. Underlayment serves as a secondary moisture barrier and helps protect the deck and provide a smooth surface for the shingles to seat against. For asbestos-cement shingles, the standard minimum is 15 pounds per square of asphalt-saturated felt. This weight strikes a balance between adequate moisture protection and practicality. Heavier underlayments, like 30 pounds, are used in more demanding conditions or with other roof types, while lighter or nonstandard weights aren’t required as the minimum for this roofing.