Closed cell spray foam is used in the rim joist areas and on top of the wall top plates in the attic. Over the top plates, it is used for its air sealing capabilities. The air barrier of the ceiling is a polyethylene sheet. The air barrier at the walls is the OSB sheathing. The spray foam connects these layers to one another to avoid air leakage between components. The ceiling air barrier gets interrupted at interior walls, so spray foam is applied over the top plates of the interior walls to connect the ceilings of adjacent rooms and prevent air leakage through interior walls. Some of the spray foam is applied before drywall installation and some of it will be done later.
|In the rim joists, the spray foam reduces heat leakage via the top surface of the concrete wall. The air sealing properties also supplement the peal and stick air barrier on the outside of the rim joist to prevent air leakage.|
|The framed exterior walls in the basement are insulated with unfaced fiberglass batts. The rigid EPS between these framed walls and the cement wall keeps the cavities warm enough to prevent condensation.|
The insulation contractor was uncomfortable using damp-spray cellulose for the house walls because the rigid foam on the outside would prevent any drying toward the outside. So, we used a blown-in fiberglass method. Fabric is stapled to the studs. Then, fiberglass is blown into each stud bay through holes in the fabric.
|This is the master bedroom with the walls and ceiling insulated. For some reason, the contractor decided to staple a layer of polyethylene on the walls after blowing in the fiberglass. That was removed before the drywall got installed.|