|Brandon Weiss of EHB (the tall one), me (center, with beer), and Jason of EcoAchievers (also with beer, speaking), warming up the crowd, while...|
|Lindsey of EcoAchievers gets the Red Door of Truth set up...|
|...for a good low reading--129 cfm!|
We calculate Air Changes per hour (that's the ACH) by multiplying our cfm reading by 60 to get cubic feet per hour, then dividing that by the house volume (18,991 cu. ft.) to get 0.41ACH50. Comfortably below the "old" 0.6ACH50 requirement. But with PHIUS+ we have a new way of expressing leakage, which is cfm of leakage per square foot of thermal envelope area. Simpler calculation: 129cfm/5664s.f. = 0.023. The PHIUS+ requirement is 0.05, so we're less than half of that--a very good result. Bravo Evolutionary Home Builders, and thanks to EcoAchievers for the testing!