With the rough wiring done, the next step in the bedroom remodeling project has been to get the space ready for insulation. Some of these steps were determined by choosing closed-cell polyurethane spray foam as the insulating material, others are based purely on my own preferences. Here are my steps in insulation prep:
Seal off roof vents and any other large openings in the roof deck or openings to adjacent spaces not part of this project. This is simply about keeping the expanding foam from going places it isn’t supposed to go. Because the foam will be installed as a “hot roof,” the insulation will be sprayed directly against the underside of the roof boards with no air channel and no need for roof vents. I’ll write more about the whats and whys of my choice of a hot roof insulation design in a future post.
Pull existing cellulose and fiberglass insulation away from the rim joist around the perimeter of the space. Although the rim is already insulated, replacing the fiberglass and cellulose with spray foam will make it better. The R-value will be improved to match the roof and walls in the rest of the crawlspace, and the closed-cell foam’s air-sealing properties will help keep warm air on the first floor from leaking outside or creating condensation problems at the sill.
Remove excess cellulose from the floor in the crawlspaces and put down plywood decking. This isn’t really necessary, but by decking the crawlspace I cut down on cellulose mess and make it easy for the foam applicators to get where they need to work. I figure the easier it is for them to move around, the less likely they will be to take shortcuts or make mistakes spraying the foam.