Garage slab insulation
New construction, uninsulated, attached garage with the garage doors and one of the walls on the exterior, the other 2 walls are interior. The garage is on the same level as the basement which is insulated from the inside. I was thinking about adding a 4′ wide strip of 4″ EPS around the 2 exterior walls, and 2.5″ EPS on the exterior garage wall (the garage doors will be insulated) to minimize the thermal bridging. With the ground temps in the center of the garage varying from high 40’s to low 60’s, I am thinking I will gain a little free geothermal so it is a little warmer in the winter and a little cooler in the summer. It will cost me very little to do that now, which is my only shot, and I will be spending a decent amount of time in the garage as it will be my makeshift workshop. If I decide to add a small mini-split in there, the foam would reduce the loads.
Thoughts?
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Replies
Jonathan,
Your comments are a little ambiguous. You wrote about your garage walls -- "I was thinking about adding a 4-foot wide strip of 4 inch EPS around the 2 exterior walls, and 2.5 inch EPS on the exterior garage wall (the garage doors will be insulated) to minimize the thermal bridging" -- and you mentioned the garage doors.
Because of the title of your comments ("Garage slab insulation"), I suspect that you aren't really talking about your garage walls. You perhaps meant to refer to the perimeter of the garage slab, not the garage walls.
If my guess is wrong, and you really were talking about the walls, here's a suggestion: Don't forget to install vertical rigid foam at the perimeter of your slab.
-- Martin Holladay
Thanks Martin.