 Because Magnolia House is airtight, fresh filtered ventilated air is supplied by an ERV system, an energy recovery ventilator, discreetly installed in a downstairs closet. This one in particular is built by a company named Brone, and it is their AI series. And it's able to provide at least 18 cubic feet per minute of fresh air for every occupant in the home, 24 hours a day, seven days a week.