For an air barrier to be effective, it needs to wrap all six sides of the "conditioned cube," and all components need to be connected in a continuous manner. The new slab was connected to the basement walls with spray foam that extended from the new basement slab to the rim sill, directly under the first floor. The corrugated housewrap became the air barrier at the exterior wall above grade, helped by the two staggered layers of foam sheathing installed over it.

At the roof-wall interface, the air barrier was transferred back to the interior at the soffit where the housewrap was adhered to the board sheathing and then connected with spray foam to the top plate of the second floor wall. It was continued with more spray foam to the interior side of the roof board sheathing.