The best way to insulate a slab is to isolate it from the ground.
Insulate concrete wall in garage.
Actually it needs to trap the cold air between the exterior wall and not let it through to your garage.
The insulation needs space to breathe.
And there is no effective way to fill the voids in an existing concrete block wall.
Your only option is to cover the inside of the exterior walls with a continuous layer of insulation as though you were insulating a basement wall.
Of unfaced expanded polystyrene r 15 that allows the foundation to dry inward and condition the space with air from inside the house.
Leave the floor above it uninsulated vapor seal the ground below with polyethylene and a thin concrete slab insulate the walls with a foam based insulation such as 4 in.
For example if you have a 7 foot wall you ll need 6 foot 10 1 2 inch long studs.
Measure the length of the wall.
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.
Cut 2 by 4 lumber to the height of your concrete wall minus 1 1 2 inches for a header and footer.
How to insulate cinderblock garages.
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.
And don t forget to take flooring into account.
Cut the 2 by 4 boards to match the wall height you wrote down in step 2.
Write the height on a piece of paper.
First mark the 2 by 4s according.
Measure the height of the wall.
Its the same thing in principal.
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.
Make a mark on the wall every 4 feet.
The second is to use a coated foam sheet like the ones manufactured by kingspan or celotex.
There are two main ways to insulate a concrete garage.
The first is to use a fibreglass insulation much like the type found in any typical loft.