Bridging in floor joist is required when?

Bridging in floor joists is utilized to enhance stability and support in the framing system. When the depth of the joists exceeds a certain measurement, in this case, 2x12, bridging becomes important to prevent excessive lateral movement.

A depth greater than 2x12 often indicates that the span of the joists could contribute to a higher risk of bending or twisting. Bridging helps distribute loads more evenly across the joists and minimizes the potential for deflection, which can compromise the integrity of the floor.

The other choices, while relevant to general support practices, do not directly pertain to the specific requirement for bridging in terms of joist depth. For example, longer spans and larger spacing might necessitate design considerations, but the explicit connection to bridging is strongest when the joist depth exceeds a particular dimension, such as 2x12. This ensures that the framing system remains stable and adequately supports the loads without undue movement.