Residential Ventilation Requirement

ASHRAE 62.2 defines whole-house ventilation requirements as 1% of the conditioned space, plus 7.5 CFM per occupant, where number of occupants is defined as the number of bedrooms, plus one.

Ventilation Requirement: (.01 x Square Feet) + (7.5 x (# of Bedrooms + 1))

Example: A 3-bedroom, 3,500 square foot home has a minimum ventilation requirement of 65.0 CFM.
(.01 x 3,500) + (7.5 x (3 + 1)) =
35 + (7.5 x 4) =
35 + 30 = 65