Shop Floor

[Mark-Ia]

Putting up a shop and need opinions on insulating under the concrete. 1" foam board or 2" foam board or no foam board? Thanks.

 

[Bob Bancroft]

Putting up a shop and need opinions on insulating under the concrete. 1" foam board or 2" foam board or no foam board? Thanks.

If you are concerned about keeping warm, are you going to put heat in the floor?

 

[neverfear]

Putting up a shop and need opinions on insulating under the concrete. 1" foam board or 2" foam board or no foam board? Thanks.

You only get one chance. If I had it to do over again, definitely 2". It breakers that thermal bond between the concrete and the ground.
You might even want to put tubing in the floor for future in floor heat.

 

[glennster]

i had concrete poured in my morton building , 60 x 110. the shop is 30x60 insulated. did the vapor barrier and 1 inch foam. 6 inch reinforced concrete, and 12 inches of concrete where i installed a 2 post lift, 11k capacity. i have a propane furnace to heat. i keep the shop at 55 in the winter unless i am working in it. i looked at in floor but i like the instant heat from forced air.

 

[NoDakInMN]

Back when I had my own heating/cooling business, when I did floor heat it was always 2" pink foam boards under the concrete and the same for 2' down around the outside perimeter of the foundation. Most of my customers had the floor heat at 60 to 65 degrees running electric boilers on off peak electric with a small gas unit heater to warm up the shop if they needed warmer.

But if I was to redo my shop, it was here when I moved in, I'd make sure I had a floor drain. Even if just drained to the outside so I could wash the floors with a hose.

 

[moresmoke]

Depends how warm you want to keep your shop. If 60F or under insulation under the floor is a waste. It would be worthwhile to put some foam around the perimeter though.

 

[jwal10]

New cabin, I put 2" of rigid foil faced under slab and 1' around perimeter as that is how thick edge is. Put vapor barrier/insulation under sheet vinyl. 3rd one and love it....James

 

[MarkB_MI]

It's most important to insulate the perimeter. When I did my shop floor, I put 2 inch insulation inside the skirt boards and under the floor within four feet of the walls. The rest of the floor I used 1 inch insulation. The gave me a six inch slab in the center and four inches around the walls. I separate the shop floor and apron with a treated 2x6 to prevent heat loss under the door.

 

[DRussell]

Back when I had my own heating/cooling business, when I did floor heat it was always 2" pink foam boards under the concrete and the same for 2' down around the outside perimeter of the foundation. Most of my customers had the floor heat at 60 to 65 degrees running electric boilers on off peak electric with a small gas unit heater to warm up the shop if they needed warmer.

But if I was to redo my shop, it was here when I moved in, I'd make sure I had a floor drain. Even if just drained to the outside so I could wash the floors with a hose.

X2 on the floor drain. Put one in my garage when I built it centered where the car sits. Can pull the car inside covered with snow/ice and it all melts and drips away with no water outside of the car perimeter.

 

[Mark-Ia]

If you are concerned about keeping warm, are you going to put heat in the floor?

No in floor heat.

 

[showcrop]

Many people who have Raynaud's syndrome didn't develop it until late in life.

 

[neverfear]

No in floor heat.

Even if no in floor heat, If you are going to use this as a shop and are going to heat it at all, putting at least 1" under the concrete will prevent or at least diminish the amount of money you spend to heat the ground under your shop. I would bet you recover the cost in 2 years or less. Your place, your call.

 

[Tony in SD]

X2 on the floor drain. Put one in my garage when I built it centered where the car sits. Can pull the car inside covered with snow/ice and it all melts and drips away with no water outside of the car perimeter.

I did the same in my garage. Sure is nice to have a warm vehicle with no snow or ice on it. And even nicer not to have a puddle in your garage.

 

[DRussell]

Many people who have Raynaud's syndrome didn't develop it until late in life.

While true, what does this have to do with a shop floor?

 

[showcrop]

While true, what does this have to do with a shop floor?

So glad you asked! When someone is middle aged, keeping their feet warm is of little concern. Once you have Raynauds, your life pretty much revolves around keeping your feet warm, and heating choices from twenty years earlier can look wrong in hindsight.

 

[mechanicfred]

Foam board under the slab keeps the floor from sweating on warm humid days. Concrete will pull moisture from the ground, at least install some sort of vapor barrier.

 

[Keith Williams]

Foam board under the slab keeps the floor from sweating on warm humid days. Concrete will pull moisture from the ground, at least install some sort of vapor barrier.

That will also help prevent radon gas from coming up if you live in an area with that problem.