Insulating existing garage floor

[rockford33]

I am currently having a house built and getting the garage slab insulated was not an option . I should say it is not "custom" built, but part of a new subdivision, so they won't/don't insulate under the slab.

I have done some reading and saw somewhere that you can insulate around the edge of the slab and that woud help minimize heat loss, etc. The garage is exposed on two sides, with the other two sides surrounded by house and the basement underneath (no basement or crawl space under the garage area). I could easily do one side of the garage (side of the house) but haven't found anywhere exactly how to do this. I saw a diagram on the web somewhere that you put extruded polystyrene about 3-4 feet down the side of the foundation, and then go 3-4 feet out from the house. Would doing only one side be any good or worth the effort? The front side would require that I pull up my driveway, so I really think I could only insulate one side of the garage.

Any thoughts, previous experiences, etc. appreciated.

Thanks,
Neil

 

[kbs2244]

Yes, insulating the exposed concrete will help keep you warmer. Don’t worry about the sides against the house, or under the driveway. They will stay warm. (Do think about insulating the garage door.)
Dig down about a foot and put one or two layers of the pink foam boards against your exposed concrete.
You will have to make some style decisions on what to cover it with. What I have seen most often is aluminum sofit material put in vertically. Then you will need a “Z” shaped top piece to go under the existing siding and out over the edge of the whatever you covered the foam with.
In Maryland I wouldn't worry about the horizonal peice going out from the foundation. That is for the guys in Manitoba.