HVAC Ventilation for General Audiences

Mechanical ventilation systems circulate fresh air into the home to replace stale and/or moist air.  For buildings that have mechanical ventilation systems installed, the IECC requires an automatic or gravity damper for any intake or exhaust protruding through the envelope. The goal is to reduce air leakage through the envelope when the ventilation system is not in operation. Health concerns make the circulation of air necessary for occupants. Mechanical ventilation system requirements achieve balance between occupant health and energy savings.