How important is it to seal electrical outlets against air leakage? Despite the tireless efforts of energy analysts and product manufacturers, nobody will ever come up with a truly valid answer to this question. One obstacle is that finding the "average" air leakage through electrical outlets is like trying to calculate the average size of rocks. Research reports and published pie charts show that air leakage through outlets can account for 15% to 25% or more of the total air infiltration in a house. But common sense tells us that the amount of air that flows through electrical outlets must depend on the tightness of the exterior sheathing and siding, the wall insulation, and the number of unsealed wiring holes