Insulating a concrete shop floor?

[Joe Cowan]

I am thinking of putting a insulated wooden floor down over my concrete floor. I am thinking about putting plastic, 2X4 pressure treated down on its face, solid sheet insulation in between the 2X4's, then 3/4 tongue and groove ply. Is this the best way? Any suggestions appreciated.

[Dan Keeling]

I would suggest putting foam sill sealer down below the 2x4 sleepers to keep the cold from conducting up from the slab. Also it may be a good idea to fir out the floor with some strips of 1/2" ply so you can use 2 inch foam sheets.

[Joe Chritz]

That is a fine way to do a wooden floor over a slab. The sill sealer is a good idea as is bumping up to 2" insulation.

In reality you just need a break from the cold concrete and 1.5" is probably plenty but it isn't hard to go the extra if you can.

A powder actuated nailer will be your new best friend.

Joe

[Michael Koch]

I am in the process of doing just that. I put a vapor barrier down and then tongue and grove plywood nailed to the concrete. At the present time I am putting down hardwood. Since I have started that, the shop has remained a steady 55-60 degrees. It makes a huge difference. I live in NC and it can get cold and damp here. MK