Re:Insulation: First the body, then the home (2011)
by Dork1234 on Tuesday January 31, 2023 @11:18AM
(#34597115)
Most homes are getting 4 to 7 air changes per hour just from leakage, 100cfm is nothing compared to that.
It should be tied to the ACH value of the construction, as well as tied to occupancy sensors in each room.
As opposed to the 0% of energy recovered when a house "breathes" (i.e., leaks like a sieve) and lets out all the conditioned air?
> That sounds good, but considering that for 'good air', you really want to be replacing the air fully every 10 minutes.
[citation needed]
ASHRAE 62.2 does not mandate nearly that much air exchange. A 2,000 sq. ft. (200 sq. m) home is about 20,000 cu. ft. of volume, and needs about 100 cfm of ventilation. And some folks (e.g., Lstiburek) think ASHRAE (at least the newer revisions) is too high:
* https://www.energyvanguard.com/blog/lstiburek-has-new-ventil...
* https://www.greenbuildingadvisor.com/article/how-much-fresh-...