Which of the following materials is suitable for use under tile roofing?

Using a two-ply membrane underlayment with interply asphalt cement is suitable under tile roofing for several reasons. This type of underlayment provides an effective moisture barrier, which is crucial in protecting the underlying structure from water infiltration. The two-ply system enhances durability and increases the overall resistance to wind uplift, which is particularly important for tile roofs that may be exposed to severe weather conditions.

Additionally, the interply asphalt cement creates a strong bond between the layers, thereby preventing the underlayment from slipping or shifting over time. This characteristic ensures the integrity of the roofing system is maintained over its lifespan. Given the weight and potential for movement of tile materials, having a robust and dependable underlayment is essential for long-term performance.

Other materials like single-layer felt or metal flashing do not provide the same level of moisture protection or structural reinforcement necessary for tile roofing systems. Plywood sheathing serves a different purpose in the roofing assembly and is not specifically designed to function as an underlayment for tile roofs. Thus, the two-ply membrane underlayment is the best choice in this context.