[mackerel]

Deal with air quality by dealing with the sources of the problem, not by having a leaky house.

My Sister in Law had some problems in her house. The builder's rep said "We think a house should be able to breath". Jeebus, man! The freaking toilet water is frozen!

A house should breath through known points of ventilation at a controlled rate, not leak like a sieve. Air leaking into walls from the living space brings warm moist air to places where it can condense, feeding mildew the water it needs to grow and make you sick.

Know your air exchange rate. Get a blower door test. I say again: Fix the problems and tighten the house. Ventilate with vents, not cracks. The money you save in heat, repair, and medical bills will be worth it.