What is the minimum thickness required for underlayment used in clay tile roofing?

The minimum thickness required for underlayment used in clay tile roofing is 3/8 inches. This thickness is essential to provide adequate support and protection for the roofing system, ensuring it can withstand the weight of the clay tiles and the elements. Underlayment acts as an additional barrier to water infiltration, and a thickness of 3/8 inches is generally considered sufficient to prevent issues such as leaks and water damage.

While the other thickness options may be useful for different roofing applications or materials, they do not meet the specific requirements for clay tile roofing as per industry standards and best practices. Therefore, utilizing a minimum thickness of 3/8 inches for underlayment is critical for the longevity and performance of clay tile roofs.