There are two main ways to insulate a concrete garage.
Insulating a concrete garage ceiling.
How to install insulation in garage ceiling for insulating your garage.
Then focus your attention on the bottom of the wall.
If you plan on using your garage for temporary activities like a mechanic or woodworking shop you would insulate both the interior and exterior walls.
And don t forget to take flooring into account.
Last chance to waterproof your wall.
So before insulating go around the garage with a can of low expanding spray foam and seal all gaps and cracks that let in the daylight.
I wrote a tutorial on how to waterproof and seal your garage walls using drylok.
Insulating a concrete ceiling the space is under a garage that is part of the house.
For example while an epoxy coating will add a protective layer to the floor it won t necessarily add insulating values.
The second is to use a coated foam sheet like the ones manufactured by kingspan or celotex.
Run a bead of silicone caulk along the bottom of the wall between the wood and the concrete.
If you didn t do that before you put the frame up you can still do it now although it s going to be.
This is part 1.
Just remember to use thicker r 40 insulation.
If there is an finished space over the garage insulate at the garage ceiling.
The first is to use a fibreglass insulation much like the type found in any typical loft.
Consider all aspects of insulating your garage not just the walls but also the garage doors and the ceiling particularly if you plan to add a heating and or cooling system.
How to insulate a garage step by step.
Here s my step by step process for how i added insulation to my garage.
Fumes can seep in underneath the wall framing where the wood rests on the concrete or block foundation.
If there is no finished space insulate at the interior wall.
Insulating the ceiling of your garage involves the same process as insulating the walls.
The ceiling is concrete panels that lay over a steel beam in the center and on the foundation walls on the perimeter.
Measure the height and width between the framing in the ceiling and pre cut the pieces you ll need.
You can insulate the walls ceiling and door of the garage to the highest r value possible but if you fail to fill those air gaps you ll still be wasting a lot of heat.