How does the thickness of the floor sheathing relate to joist spacing?

The correct answer indicates that as the spacing between floor joists decreases, the thickness of the floor sheathing increases. This relationship is based on structural support requirements. When joists are spaced further apart, the floor sheathing must be thicker to maintain structural integrity and distribute loads across a wider span. Thicker sheathing helps prevent issues such as sagging or bending under weight, ensuring a safe and stable floor.

Conversely, if the joists are spaced closer together, the floor sheathing does not need to be as thick because the support provided by the joists is more frequent, allowing the load to be distributed more effectively without requiring additional thickness for strength. Understanding this relationship is crucial for ensuring the safety and durability of floor systems in construction.