New shop new stove

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Michaelsehlke

New Member
Jun 1, 2018
2
Missouri
i recently built a new 24x30 garage. It is somewhat insulated with a wrap that has an R value of like 3. I also have a concrete floor. I’m not looking to heat it constantly but except on the weekends and evenings when I’m working out there. I’m tore as to getting a wood stove as compared to a furnace. I want something with a blower for sure. It does get rather cold in north central Missouri. Wood consumption and burn time don’t really matter I just want something big enough yet not overkill. Any help is appreciated!
 
I have a similar size garage in Northern NH. Its got a bit more insulation but its not in any way tight. I have a very old "wood furnace" instead of a wood stove. Its basically a wood stove enclosed by a sheet metal box on all sides except the front. There is blower on the back that sucks in room air and a 10" duct on the top of the box that was intended to hook into a hot air system. Its a bottom grate design where combustion air come in under the grate. It definitely warms up the air and circulates it around the room. I had a regular wood stove before and it took a lot longer to heat up the garage plus the the heat was lot more uneven as a regular stove heats a lot through radiant heat versus convection. I though I would need ductwork but it circulates naturally.

I usually start the stove and run a jet heater for about 15 minutes. By then the stove has heated up and the fan kicks on. Once the fan kicks on I, I turn off the jet heater and will rapidly be shedding clothes in another 15 to 20 minutes. Within an hour or two, I usually need to crack a door open as its too warm. My stove has a very poor air damper arrangement so it doesnt idle very well.

The closest thing I can find to my rig is one of these https://www.lowes.com/pd/Summers-He...MI_6SS-Zey2wIVkgOGCh0njAVqEAQYAyABEgJr3fD_BwE My rig is far more primitive and I got if for free so I live with it.

I think someone could easily convert a fisher type stove into something similar. The only tricky part is installing a snap switch to cycle the blower.
 
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I have a similar size garage in Northern NH. Its got a bit more insulation but its not in any way tight. I have a very old "wood furnace" instead of a wood stove. Its basically a wood stove enclosed by a sheet metal box on all sides except the front. There is blower on the back that sucks in room air and a 10" duct on the top of the box that was intended to hook into a hot air system. Its a bottom grate design where combustion air come in under the grate. It definitely warms up the air and circulates it around the room. I had a regular wood stove before and it took a lot longer to heat up the garage plus the the heat was lot more uneven as a regular stove heats a lot through radiant heat versus convection. I though I would need ductwork but it circulates naturally.

I usually start the stove and run a jet heater for about 15 minutes. By then the stove has heated up and the fan kicks on. Once the fan kicks on I, I turn off the jet heater and will rapidly be shedding clothes in another 15 to 20 minutes. Within an hour or two, I usually need to crack a door open as its too warm. My stove has a very poor air damper arrangement so it doesnt idle very well.

The closest thing I can find to my rig is one of these https://www.lowes.com/pd/Summers-He...MI_6SS-Zey2wIVkgOGCh0njAVqEAQYAyABEgJr3fD_BwE My rig is far more primitive and I got if for free so I live with it.

I think someone could easily convert a fisher type stove into something similar. The only tricky part is installing a snap switch to cycle the blower.
I never really considered a furnace for a garage. Thanks for posting. I think that's a great idea.
 
For your use, no stove will be too big as far as heat output.
 
cheap box stove and a sheet metal box around it to act as a plenum - witch might help with various code problems that could arise as you are calling it a garage ( if you refer to it as a barn or shop that gets around some code problems) but then that might lead to other issues depending on local rules.
 
I'd be looking at a basic wood furnace from Englander, Drolet, etc..
 
I have a 1200 sq.ft. heated shop, and after considering my usage and running the numbers, went a completely different direction: mini-split.

With auto-changeover thermostats, having heat setting = 55F and cool setting = 80F, I spend damn near zero dollars to heat and cool it. But it stays dry and comfortable in there, and I’m not waiting 3 hours for a wood stove every time I want to go out there and work for 1 hour. I also don’t need to worry about equipment rusting when the stove cools and RH% rises in the shop.

Last night, I went out at 9:30pm to shoot paint on a mower deck. Bumped the t’stat down to 65F to keep it cool and comfortable while I wore the bunny suit for spraying. Humidity outside was so high it would’ve rained if I sneezed, but it was dry and comfortable in the shop.

Similarly in the winter, most evenings I go out there to do something, I’d waste more time getting the stove started than I plan to spend out there. The mini-split starts blowing hot or cold air instantly.

I’m so glad I didn’t waste the space and time on installing a wood stove out there.
 
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In contrast, I often go out to the shop just for the pleasure of burning a nice fire. Proper insulation keeps temperatures quite steady so no humidity problems in my shop.

Cooling would be nice for a few days of the year and automated heating would also be nice when I’m out of town.

Just like our homes, we would ideally have both a wood heater and then a backup thermostatic heat source.
 
I'd be looking at a basic wood furnace from Englander, Drolet, etc..

Why on Gods green earth would you recommend that. wood eatin smoke and creosote makin dragons
 
I have a 1200 sq.ft. heated shop, and after considering my usage and running the numbers, went a completely different direction: mini-split.

With auto-changeover thermostats, having heat setting = 55F and cool setting = 80F, I spend damn near zero dollars to heat and cool it. But it stays dry and comfortable in there, and I’m not waiting 3 hours for a wood stove every time I want to go out there and work for 1 hour. I also don’t need to worry about equipment rusting when the stove cools and RH% rises in the shop.

Last night, I went out at 9:30pm to shoot paint on a mower deck. Bumped the t’stat down to 65F to keep it cool and comfortable while I wore the bunny suit for spraying. Humidity outside was so high it would’ve rained if I sneezed, but it was dry and comfortable in the shop.

Similarly in the winter, most evenings I go out there to do something, I’d waste more time getting the stove started than I plan to spend out there. The mini-split starts blowing hot or cold air instantly.

I’m so glad I didn’t waste the space and time on installing a wood stove out there.

Philly is far from the environment that the OP is from. Winter isn't exactly winter down there.
 
Why on Gods green earth would you recommend that. wood eatin smoke and creosote makin dragons

The englander furnace is just an nc30 with a shell. It burns cleaner than my catalytic blaze king. The drolet furnaces are also epa certified. You’re probably thinking of the old illegal smoke dragons?
 
The englander furnace is just an nc30 with a shell. It burns cleaner than my catalytic blaze king. The drolet furnaces are also epa certified. You’re probably thinking of the old illegal smoke dragons?

When some one says wood furnace I'm thinking like my buddies Clayton, I had a Charmaster years back, I was thinking of starting my own black top business. I've never seen a stove crap up a chimney as quick as that thing would
 
Philly is far from the environment that the OP is from. Winter isn't exactly winter down there.

I assume you must be kidding, as it’s colder where I live, than any city I’ve checked in Missouri.

Mine:

9cd83e53b8f3a060854f60b7863d6a50.jpg

Kansas City:

b4242b3ef7ad4185a65e71f8d3843e51.jpg

At most, you could say the OPs climate is fairly similar but warmer than me, it’s not like he is in Alaska. And I’m not in Philly proper, it pays to keep the riff raff unaware of ones exact location.
 

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I have a similar size garage in Northern NH. Its got a bit more insulation but its not in any way tight. I have a very old "wood furnace" instead of a wood stove. Its basically a wood stove enclosed by a sheet metal box on all sides except the front. There is blower on the back that sucks in room air and a 10" duct on the top of the box that was intended to hook into a hot air system. Its a bottom grate design where combustion air come in under the grate. It definitely warms up the air and circulates it around the room. I had a regular wood stove before and it took a lot longer to heat up the garage plus the the heat was lot more uneven as a regular stove heats a lot through radiant heat versus convection. I though I would need ductwork but it circulates naturally.

I usually start the stove and run a jet heater for about 15 minutes. By then the stove has heated up and the fan kicks on. Once the fan kicks on I, I turn off the jet heater and will rapidly be shedding clothes in another 15 to 20 minutes. Within an hour or two, I usually need to crack a door open as its too warm. My stove has a very poor air damper arrangement so it doesnt idle very well.

The closest thing I can find to my rig is one of these https://www.lowes.com/pd/Summers-He...MI_6SS-Zey2wIVkgOGCh0njAVqEAQYAyABEgJr3fD_BwE My rig is far more primitive and I got if for free so I live with it.

I think someone could easily convert a fisher type stove into something similar. The only tricky part is installing a snap switch to cycle the blower.
I have a similar size garage in Northern NH. Its got a bit more insulation but its not in any way tight. I have a very old "wood furnace" instead of a wood stove. Its basically a wood stove enclosed by a sheet metal box on all sides except the front. There is blower on the back that sucks in room air and a 10" duct on the top of the box that was intended to hook into a hot air system. Its a bottom grate design where combustion air come in under the grate. It definitely warms up the air and circulates it around the room. I had a regular wood stove before and it took a lot longer to heat up the garage plus the the heat was lot more uneven as a regular stove heats a lot through radiant heat versus convection. I though I would need ductwork but it circulates naturally.

I usually start the stove and run a jet heater for about 15 minutes. By then the stove has heated up and the fan kicks on. Once the fan kicks on I, I turn off the jet heater and will rapidly be shedding clothes in another 15 to 20 minutes. Within an hour or two, I usually need to crack a door open as its too warm. My stove has a very poor air damper arrangement so it doesnt idle very well.

The closest thing I can find to my rig is one of these https://www.lowes.com/pd/Summers-He...MI_6SS-Zey2wIVkgOGCh0njAVqEAQYAyABEgJr3fD_BwE My rig is far more primitive and I got if for free so I live with it.

I think someone could easily convert a fisher type stove into something similar. The only tricky part is installing a snap switch to cycle the blower.
I have an old blaze King ktj 302 with blower I had in my old shop that was 18x21 without concrete and it done a decent job but my old shop didn’t have a truss roof and wasn’t as big of course. I could really get the old king cooking with some maple or ash but I don’t think it has near enough blower for my new shop. What Size blower do you have?
 
Before you worry about a blower, a very key thing to heating a garage is you need to a have a ceiling. Otherwise all the heat goes up in the trusses. If you have open trusses you are trying to heat the outdoors. The ceiling doesn't need to be insulated it just needs to stop air flow to get most of the benefit. Years ago I used to heat a un-insulated garage with a jet heater and it did not work very well until I put up a sheet of plastic on the ceiling. That made a major difference. My ceiling is mostly salvaged HVAC duct board. Its compressed fiberglass board about 1" thick with heavy foil face on it. I got it for free from a contractor that was replacing a duct system. I nailed it up to the ceiling joists and sealed up the joints with duct tape. Doesn't look great as its patched up but really keeps the heat in. I know some folks who have just put up cardboard but I don't recommend it due to flammability. One wall of the garage is covered with 1/2" PVC signboards from my old employer. I have the logo facing into the walls.

With a ceiling, the outlet of the wood stove duct hits the ceiling and radiates out, the blower suck cold air near the floor and a natural thermosyphon starts up Warm air runs to the out edges of the ceiling then cools down and drops down the walls and then runs across the floor back to the blower. Duct work can speed things up but without a flat ceiling in place it just doesn't work as well.

I have seen folks try to push the heat down from an open truss roof with ceiling fans but it doesn't work very well if the roof isn't insulated. I also have seen creative systems to catch the heat up near the ridge pole and pump it down but nothing really works that well in a poorly insulated structure as heat rises.

On construction jobs where distribution is needed they use temporary perforated polyethylene ducting http://www.tombling.com/ducting/. The blower inflates the duct and the holes distribute the air. I don't need duct as my blower on the stove seems to cover it. Grainger has all sorts of blowers if you need one.

By the way, temps get down to -20 F in winter in my area and I have no problems getting the garage warm. The biggest hassle is dealing with the water melting off my vehicles as the ice and snow that inevitably collect under them melts.
 
Before worrying about any of this check with your inspector and insurance company to see if you can even put a wood stove in there. Most areas it is not allowed bit as long as your insurance is ok with it you can usually get away with it.
 
When some one says wood furnace I'm thinking like my buddies Clayton, I had a Charmaster years back, I was thinking of starting my own black top business. I've never seen a stove crap up a chimney as quick as that thing would

There's a whole big wide world of clean furnaces out there aside from your buddys Clayton. Or a Charmaster.
 
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i recently built a new 24x30 garage. It is somewhat insulated with a wrap that has an R value of like 3. I also have a concrete floor. I’m not looking to heat it constantly but except on the weekends and evenings when I’m working out there. I’m tore as to getting a wood stove as compared to a furnace. I want something with a blower for sure. It does get rather cold in north central Missouri. Wood consumption and burn time don’t really matter I just want something big enough yet not overkill. Any help is appreciated!

Is there insulation under the floor?
 
And, mini splits go to resistance heat (very high consumption) below +/- 10 °F.

Are you sure about that?

I pretty well have given up getting people to realize that a standard household heat pump is not the same as cold source minisplit heat pump. Even that distinction is not black and white as some household heat pumps seem to be having some capability of operating below freezing temps and some minisplits are not cold source and also don't heat very well much below freezing.
 
And some mini-split do not have resistance heaters.
 
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The water from melt in the garage will just evaporate as the stove burns and help to humidify the space. If it is extreme amounts just get a garage squeegie and once fully melted, open the garage door a few inches an push it out and close the door. If the floor was put in with any thought at all, it should have a pitch toward the door for drainage anyway. The water that drips from your car and all the salt came from the outdoors anyway did it not? How many mega-tons of salt run off into streams and lakes every year? Salt is natural, and as it turns out necessary.
 
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