That s not always possible especially in existing construction but if you re able to build a finished floor inside your garage you can insulate on top of the slab.
Should i insulate my garage floor.
It s not a difficult job although it will take some time and you ll need the proper materials in order to properly insulate the garage floor.
If you are converting your garage to living space and plan to install a new floor it is usually smart to begin by insulating the concrete floor.
You might also choose to insulate a garage floor if you plan to use the garage as a workshop even if you are still storing vehicles in it.
As apart of the insulating process you ll want to look into weather stripping doors and windows of your garage to truly keep the energy kept indoors and be sure to finish your project by caulking.
However there are many other benefits you can expect from this easy diy improvement.
Use fibreglass cellulose foam board or closed cell spray foam if it were my garage i d go with spray foam.
Sealing off gaps around the exterior and interior of your detached garage will truly insulate it to the best of your abilities.
Not only will this make it warmer but the floor will be a lot safer than bare concrete.
But if the garage is heated you should definitely insulate.
Then cover it with drywall.