Where to put the vapor barrier?
I am in the Seattle area (climate Zone 4) and am going to be putting in an “addition” for a new utility room and I would like to double check the location of moisture control here’s the setup:
Slab above grade is the garage floor, which is 1-3″ below the top of the foundation walls. I plan on putting pressure treated scribed 2×12 floor joists down to 1) raise the level of the floor to the existing floor heigh in the rest of the house; and 2) allow for insulation to be put between the joist bays which would otherwise be open space.
I was thinking of putting 6 mil. barrier down on the concrete slab, then the PT joists, 1″ rigid foam (on the 6mil. barrier) between the joists and then unfaced fiberglass between the rigid foam and the subfloor (3/4″ plywood), over which a tile floor will be installed.
Does this sound Ok? I’ve seen a lot of contradictory advice when it comes to this!