Really tight homes have HRV units (heat recovery ventilator). Well, they 'used' to be called HRV, now they are calling them ERV's (energy recovery ventilator). They are required in some homes, or you could quite possibly die in your sleep. I have one in my home that I installed when I built it in 99. I was able to get some points for installing one, which applied to a credit reduction program for energy efficient homes (4 star, 5 star, 5 star +).

http://www.hvacquick.com/products/commer...ery-Ventilators

Last edited by michael_d; 01/10/15 08:08 PM.