Advice on indoor furnace/stove build

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Amo86

New Member
Dec 3, 2020
3
Maryland
Im looking for advice on furnace stove build for our farm shop. The building is 50x100x16 R-19 on walls and aprox R30 in ceiling located in central Maryland. I have welding and fabrication experience and a stack of 1/2" and 5/16" plate thinking large fire box with heavy wall pipe above in fire box as heat exchanger with old furnace fan blowing throughthe pipes many guys around here use double barrel stoves want to build one nice stove that will last me the rest of my days any advice is much appreciated. I already have a 8" chimney in place with old baker stove that dont cut the mustard.
 
If your barn is insured, I doubt your insurance company will insure the building if you have a home built wood furnace.
 
If your barn is insured, I doubt your insurance company will insure the building if you have a home built wood furnace.
If your barn is insured, I doubt your insurance company will insure the building if you have a home built wood furnace.
You may be right farmer down roads barn burnt to total loss using double barrel stove and they covered everthing.luck of the draw But this is why i want to build out of heavy steel and quality avoid fire at all cost. According to most posts i see here even a store bought stove would not be covered.
 
Thought #1: That's a big space. Definitely calculate your BTU heat load - I suspect that if you want to make it a comfortable space with 55*F+ temps in winter, you'll need more than one heat source and a bank of ceiling fans to keep the warm air circulating.

Here's a good BTU calculator.U se the second one down - the top one is just for AC: https://www.calculator.net/btu-calculator.html

Thought #2: For both insurance purposes and practical useage, I'd buy a furnace or woodstove rather than try to make one. Insurance usually requires a UL listing and a documented, to-code install. To get an efficient burn with secondary combustion is more challenging than it seems and buying a commercial product will give you the best efficiency and performance.
 
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Thought #1: That's a big space. Definitely calculate your BTU heat load - I suspect that if you want to make it a comfortable space with 55*F+ temps in winter, you'll need more than one heat source and a bank of ceiling fans to keep the warm air circulating.

Here's a good BTU calculator.U se the second one down - the top one is just for AC: https://www.calculator.net/btu-calculator.html

Thought #2: For both insurance purposes and practical useage, I'd buy a furnace or woodstove rather than try to make one. Insurance usually requires a UL listing and a documented, to-code install. To get an efficient burn with secondary combustion is more challenging than it seems and buying a commercial product will give you the best efficiency and performance.
Thought #1: That's a big space. Definitely calculate your BTU heat load - I suspect that if you want to make it a comfortable space with 55*F+ temps in winter, you'll need more than one heat source and a bank of ceiling fans to keep the warm air circulating.

Here's a good BTU calculator.U se the second one down - the top one is just for AC: https://www.calculator.net/btu-calculator.html

Thought #2: For both insurance purposes and practical useage, I'd buy a furnace or woodstove rather than try to make one. Insurance usually requires a UL listing and a documented, to-code install. To get an efficient burn with secondary combustion is more challenging than it seems and buying a commercial product will give you the best efficiency and performance.

Yes 50s would be great working conditions. I have intentions of getting outdoor furnace for the farm house and shop but that's couple years out. The chimney company that did the install said there is no wood stove permits or inspections in my county " carroll" im going to try to attach a link to stove I like that I feel would work for me i just feel better about heavy steel over a oil tank. Have 4 large ceiling fans in place now.
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You may be right farmer down roads barn burnt to total loss using double barrel stove and they covered everthing.luck of the draw But this is why i want to build out of heavy steel and quality avoid fire at all cost. According to most posts i see here even a store bought stove would not be covered.
I think you are right. My buddy's cousin was using a double barrel stove to heat his barn and the insurance company didn't cover his loss.

I have a wood burning furnace in my house and my insurance company is okay with it but the furnace had to be UL certified for them to insure it along with my house. I also had to send them a picture of the furnace, and the UL label on the furnace.
 
I have intentions of getting outdoor furnace for the farm house and shop but that's couple years out.
Since this is the case, if you are willing to take the insurance risk in using a homemade stove, I'd use a double barrel stove or two until you get that OWB set up. That steel plate is worth too much to use up on an experiment like this IMO.