"You know where this is going, right? Codes will eventually require balanced ventilationMechanical ventilation system in which separate, balanced fans exhaust stale indoor air and bring in fresh outdoor air in equal amounts; often includes heat recovery or heat and moisture recovery (see heat-recovery ventilator and energy-recovery ventilator). ." I've heard people say this more than once in the past year or so. As someone who has been attending the semiannual meeting of the ASHRAE 62.2A standard for residential mechanical ventilation systems established by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers. Among other requirements, the standard requires a home to have a mechanical ventilation system capable of ventilating at a rate of 1 cfm for every 100 square feet of occupiable space plus 7.5 cfm per occupant. committee, I've been skeptical. Then I read the new Aspen energy code and saw the first evidence that this really could happen.
from Building Science http://www.greenbuildingadvisor.com/articles/dept/building-science/should-balanced-ventilation-be-required