The above variable air volume (VAV) supply air system fan requires 20,500 cfm @ 3 in.w.g. SP, which includes 400 cfm or 2 percent estimated duct air leakage.

The VAV boxes need a minimum of 1 in.w.g. at the box inlet, rectangular and flat oval duct aspect ratios cannot exceed 3:75 to 1.

Ductwork shall be sealed as per ASHRAE/SMACNA seal classes B for 3 in.w.g. and C for 2 in.w.g. construction pressure classifications.

All elbows will have RiD = L5, transitions = 30° slope, branch taps = 45° angle with 45° elbows, and wye fitting = 45° angles with 45° elbows.

All duct branches to VAV boxes have balancing dampers.

All ductwork will he galvanized steel with gauges and reinforcement as per the SMACNA 111/AC Duct Construction Standards 1985.