Heated shop floor

In the next few years I would like to install a heated floor system in a building we use for repair work. The building was not built originally for that purpose but can be economically converted.
The question relates to square footage. Would like enough space to pull in smaller 6 row combine or 6 row planter with tractor attatched and close the door. Space availability in the building for said machines is not an issue. Is the cost per square foot per month for the energy inexpensive? Would like the utility bill for the needed shop area 35 x 25 feet to come in at 100 dollars a month or under. I would partition less of the remainder of the building into "cold" area as long as I could maintain a budget. For discussion sake, the building would be adequately insulated .
I have heard the salesmen talk and can't seem to find people who have the time to talk about it in their own buildings. Would like to hear from people with some experience on this.

I don't have one,but I have a theory of my own on one. My brother says it's legal to do this. I thought if you were to drill 2 2inch wells. Pull the 50 degree water from one,route it through tubes in the floor and then back down the other well,even keeping it at 50 degrees,with coveralls and longjohns,it would feel pretty good in there this time of year. You could cool it down in the summer that way too. He says that as long as it's a closed system,it's OK to run that water back into the gound that way. Only drawback would be,you'd never want to let it shut off in the winter or you'd have a frozen mess.

All the heated floors that I have seen work best with a sand base and then a layer of styrofoam. Then a grid work of tubes with concrete over them.

Might want to put in a vertical piece of styrofoam along the foundation, as well as the sand covered by two inch styro for the floor. On our basement, I laid cattle panel with six inch spacing, and tied the tubing to it, laid 12 inches apart. Took picture of it- can be used as a reference when adding interior walls, etc. so nails are not over lines. Now there are simpler ways to attach the tubing, but still use styro.

Hi; I have had a heated shop floor for 3yrs now(2350 sq.ft) and it has worked grt! 1' by 1' poured around the edge, 8" thick. 12'' sand and 2'' pink foam. Then 3 1/2 rebar around the edge, with 6' square grid in the inside. Then, 4x12 hiway mesh to tie 9 300' runs of pex tube. Also on the outer edge of the concrete, is 2'down, and 2' out of pink. I ran some tube under the outer edge of the overhead doors to keep them from freezing. Barn cats really like this!! 4mil plastic under the floor also. Also on the walls, with 6'' of insalltion, and I blew at least 3 to 4 FEET of cellose up in the rafters. What a difference that made. 4mil plastic on ceiling. Used white steel inside. 33BELOW 0 this morning...55 wind chill, (northern mn) We have 80' of clay soil here... The posts sit on the slab...not in the grd!! Lots of money spent where you can't see it!! Oh, we heat the shop and house with a outside wood fired boiler. So, don't know what it would cost to "pay" to heat all this. Well, other than a dozer to make logging roads, tractor to skid, 4 chain saws, and you get to be, "outstanding in your field" at 30 below! Pay me now, or pay me later! Oh yea, so far I've used 26 gallons mixed gas. We have always heated with wood and like to do it. Thanks Bobmn

Good idea!

Geothermal heat technology seems like the way to go.................

I don't have one. Wish I did. The people I know who have them say they love them and are really glad they did it!
Pastor Mike

This is my first hand knowlage with heated floors.Every place that I have tile in the house the floor is heated. I almost did not do it beacouse of the price. My brother had told me onetime "If you ever put tile in your house make sure it is heated".So,on his advice I did it.The first time I walked on that warm floor in my bare feet it was worth every penny.I know you will not be in the shop in bare feet,but,if your feet are warm your whole body is warm.

I'll tell you laying working on a 50 degree floor isn't warm. Keeping a floor at 80 F feels nice.

To the original poster, is the goal to heat the shop or to heat the floor so its warm to work on it? Your fuel costs will follow.

A friend of mine has his heated that way. He says the only problem is the floor is dusty. He uses a floor sweep material when he sweeps it up. He also heats with wood, so no idea of the cost.

I have about 2300 feet to heat up here in SD. COncrete floor, 6 inch sidewall with insulation,under 5/8 particle board interior walls. tin ceiling at 12 feet with blown in insulation on top. Two 20 foot insulated overhead doors.
One 150K Reznor propane heater hanging on back wall. Electronic thermostat. Keep the shop at 40 degrees from 6pm to 8am. Then run it up if I'm working there, Will heat up to 58 degrees or so in about 20 minutes.
I use about 400 gallons of propane on the year.
DOn't use hardly any from mid April to mid Nov.

Not Styrofoam, for this type of installation, you have to use POLYSTYRENE the stuff that snaps/pops
when you break it.

When I did mine in Wi. I got a pamphlet from NDSU extension service, "HOT WATER FLOOR AND SPACE HEATING". I don't know if it is still available.
I hooked up 2 waterheaters, one gas one electric and circulated hot water thru pipe in the floor. Found out I only needed one at a time This was clark electric , a coop in clark county. Polystyrene under the floor, 4' in the ground on the perimeter,8" fiberglass batts in the walls, and about 20" fiberglass blowing insulation over a steel ceiling. 20'X 36' 14' ceiling well under $100 a month to heat it.
NDSU plans

We"re into the first winter with our "new" shop, 40x40ft, we have infloor heat, powered by a geothermal heat pump, 1600ft of pipe in the floor, and approx 3600ft pipe in trenches outside. The workshop is a pole barn (4ft on center) insulated with 6inches of spray foam insulation in the walls/ceiling, and 2inches of insulation under the concrete (R10 - Styrofoam - rated for below grade use). So far this winter, heating costs have been around $140/month, with electricity cost me around 6cents per kWh. We have had below av. temps up here in Canada the last month or so... Hope that is some help to you.

I installed ours similar to the above with a few exceptions. I put the pex in on 3' spacings because in the start the floor heat was only meant to be supplementary. Also, I did not use "Styrofoam SM" under the slab because it would cost too much and as noted the floor heat was only meant to be sup. I did put SM under the floor for the first 4' around the edges and for 2' down the outside of the rat wall. Also, we have 16" of topsoil that I removed and replaced with packed sand and then put another 16" of A gravel on top of that (with geo-fibre between the sand and gravel) and then the 8" of concrete with pex.

We have found that if we get the shop to 55*F it is just right to work in coveralls. Feet that are not cold make a big difference, as noted.

We also found that the 3' spacing is good enough to heat the building, never had to add the other heaters that I planned to. However, the barn doubles as vegetable storage and it helps to have all the thermal mass of the 'taters in there.

Our building is 5000 sq ft with R30 walls and R40 ceiling.

Good Day,
JP.

I've thought about that too. Problem is a 55F concrete floor will be running a river of condensation water during humid summer days.