What is the maximum air capacity for panned joists that are 16 inches on center using 8-inch joists?

The maximum air capacity for panned joists, such as those that are 16 inches on center, is determined by the size of the joists and the specific configurations established in the mechanical code. In the case of 8-inch joists, the capacity is closely associated with how efficiently air can be transported through the panning created by those joists.

The correct answer reflects the established guidelines in the code which typically indicate that, for 8-inch joists spaced at 16 inches on center, the maximum air capacity is 375 cubic feet per minute. This figure is crucial as it ensures that airflow is optimized for heating and cooling systems installed in residential and commercial buildings, preventing issues such as insufficient airflow or excessive pressure drop.

This standard is based on calculations that account for the size of the panned joists as well as their spacing, ensuring that the design adheres to safety and efficiency standards in HVAC systems.