What is the minimum underlayment for wood shingles?

What is the minimum underlayment for wood shingles?

• A. 15 lb
• B. None required
• C. 30 lb
• D. 60 lb

Answer: (B)

Wood shingles provide the primary weatherproofing when installed correctly, so a separate underlayment isn’t required in the standard installation. The shingles’ overlapping pattern sheds water, and a deck that’s dry and properly prepared is typically sufficient without a secondary moisture barrier. Adding underlayment can even be unnecessary or problematic if it traps moisture between layers. Therefore, the minimum underlayment in this common scenario is none. Always follow manufacturer instructions and local codes if conditions call for additional protection, but in the typical wood-shingle installation, no underlayment is mandated.

Wood shingles provide the primary weatherproofing when installed correctly, so a separate underlayment isn’t required in the standard installation. The shingles’ overlapping pattern sheds water, and a deck that’s dry and properly prepared is typically sufficient without a secondary moisture barrier. Adding underlayment can even be unnecessary or problematic if it traps moisture between layers. Therefore, the minimum underlayment in this common scenario is none. Always follow manufacturer instructions and local codes if conditions call for additional protection, but in the typical wood-shingle installation, no underlayment is mandated.