When using plywood as a roof deck material, what nominal thickness is recommended for 24-inch rafter spacing?

When utilizing plywood as a roof deck material with 24-inch rafter spacing, a nominal thickness of 5/8 inch is recommended to ensure structural integrity and proper load distribution. This thickness provides adequate support for the roofing materials, reduces the likelihood of warping or sagging under weight, and meets building code requirements for stability. A 5/8 inch plywood deck is robust enough to handle the typical loads encountered in roofing applications while accommodating any potential movement due to temperature changes or moisture.

Thicker plywood would also be acceptable, but it's essential to balance material cost and weight with structural needs. Thinner options, such as 1/4 inch or 1/2 inch, would not provide sufficient strength for the 24-inch spacing, increasing the risk of structural failure. Therefore, using 5/8 inch plywood strikes the right balance for effective roofing performance.