Matt Stetar
One thing to think of is the insulation under your
slab so the heat does not wick away. you can pour the cement over 3" blue foam like I did or fill the hole with small rock and insulate out side. This can be done by digging down below the frost level where you live and add the foam insulation out side the building. I have cement wall on a footing 20" wide 10" thick and the wall is keyed to set on the footing. I used an 8" cement wall and then the 6" wood studs with 6" pink and 1.5" foam under the sideing. I just got a power bill a few days ago and see with the new electric boiler I`am paying around $10.00 a day to heat my shop and power for the house.The power rates went up here but I `am using less power than last year. If you plan to use an out side boiler I would add a few storage tanks in the shop , this way the boiler would not have to be used 24/7 . The temp you choose to have in your shop will determine the temp of the water to heat the cement.You will need a temperature control valve to blend the water as it is pumped back into the floor. I think my cement is just a few deg warmer than what I have the thermostat set at. Say three 80 gallon tanks connected to a boiler would heat the building for hrs with no fire in the boiler.my friends house is 28'x58' and he uses two 60 gallon tanks .they only heat the tanks at off hrs (11 pm to 6 am)off the power grid. So 1 fire up a day could heat a big shop if it was done correctly. I would use an open system from the boiler to the tanks and then closed at 10 psi for the floor, this way you will have a good flow and no cold zones. Now that I don`t have a tank to heat my water I run a closed system at 10 psi in the floor. later Don T
One thing to think of is the insulation under your
slab so the heat does not wick away. you can pour the cement over 3" blue foam like I did or fill the hole with small rock and insulate out side. This can be done by digging down below the frost level where you live and add the foam insulation out side the building. I have cement wall on a footing 20" wide 10" thick and the wall is keyed to set on the footing. I used an 8" cement wall and then the 6" wood studs with 6" pink and 1.5" foam under the sideing. I just got a power bill a few days ago and see with the new electric boiler I`am paying around $10.00 a day to heat my shop and power for the house.The power rates went up here but I `am using less power than last year. If you plan to use an out side boiler I would add a few storage tanks in the shop , this way the boiler would not have to be used 24/7 . The temp you choose to have in your shop will determine the temp of the water to heat the cement.You will need a temperature control valve to blend the water as it is pumped back into the floor. I think my cement is just a few deg warmer than what I have the thermostat set at. Say three 80 gallon tanks connected to a boiler would heat the building for hrs with no fire in the boiler.my friends house is 28'x58' and he uses two 60 gallon tanks .they only heat the tanks at off hrs (11 pm to 6 am)off the power grid. So 1 fire up a day could heat a big shop if it was done correctly. I would use an open system from the boiler to the tanks and then closed at 10 psi for the floor, this way you will have a good flow and no cold zones. Now that I don`t have a tank to heat my water I run a closed system at 10 psi in the floor. later Don T