(Equivalent leakage area-technically this is a calculated, extrapolated number used for energy modeling, but for your purposes you can think of it as the size of a theoretical hole in a wall if you combined all the air leakage points in a house into one spot at a pressure of 10 Pascal.)

This metric allows for simple communication as crews, sub-contractors, and homeowners can often relate to the size of a hole in square inches better than trying to imagine CFMs of air flowing through multiple small leaks. Using the 2,000-square-foot house again, a really tight house would be less than 80 square inches of leakage. (A sheet of 8.5×11 paper.)