Best option to heat a large space?

[AeroncaDriver]

Have a large metal building, partially insulated, in Northern Arkansas. Average temps in winter are around 30F, but are often in the teens. Would like to make the space comfortable before next winter, and by comfortable, I mean tolerable enough to go out and work for a couple hours in the evenings. 45F inside when it is 25F outside would be nice. Building is 3000 sq ft with 16 ft side walls and a 26 ft peak. Problem is that propane and natural gas are not available, as the building is located down a goat trail in a valley. I do have 240V single phase, and could carry in as much diesel fuel as needed. Have looked at some indirect fired diesel heaters, but they seem to have iffy reviews. It would take several 10,000W electric heaters and a boat load of cash to run them, plus I don't know how I feel about Chinese electrical anything intentionally getting hot. Would a circulation fan near the roof help more than I think it would? Does anyone have suggestions?

 

[Noltz]

Sounds like an oil furnace or two is what you're looking for. Yes the fans help, even with 16' ceilings so 26' is a LOT of open space to heat. There's also waste oil furnaces.

 

[PoorUB]

Why not just a typical residential oil furnace? Building a chimney would be an issue, but it would give off clean heat.

Pour a footing for a masonry chimney, and buy concrete chimney blocks and flue liner and get to work. Or, and I never said this, ;-) find a heavy wall 8" steel pipe and use it for a chimney!

 

[Sumboodie]

Depending on your electric rates, that may be the cheapest.

 

[Sumboodie]

Why not just a typical residential oil furnace? Building a chimney would be an issue, but it would give off clean heat.

Pour a footing for a masonry chimney, and buy concrete chimney blocks and flue liner and get to work. Or, and I never said this, ;-) find a heavy wall 8" steel pipe and use it for a chimney!

The high efficiency units are usually direct vent.

 

[PoorUB]

The high efficiency units are usually direct vent.

High efficiency oil?

 

[Phuckin' Jim]

Another option would be a big-*** wood stove, or wood furnace.
Especially if there's a lot of deadfall near that building.

 

[Walkers]

A wood stove in a shop that size can’t be beat. Just check with your insurance guy first.

 

[Shiftless]

Do you really need to heat the entire space? 3000 sq. ft. With 16 foot ceilings and only partial insulation is VERY hard to heat unless you can generate several hundred thousand BTU’s.
Is there a way to divide the space so you can work in only part of that space? What tasks do you want to accomplish in the winter months? Divide and insulate only part.

 

[Sumboodie]

High efficiency oil?

93%

 

[billconner]

More insulation would save a lot of energy.

 

[PoorUB]

93%

Who manufactures a 93% oil furnace. I have never heard of any thing over about 83%.

 

[danski0224]

If you are seriously considering electric resistance heat, a heat pump would be a much better choice.

 

[Yankeefarmer]

Take a hard look at a cold weather capable heat pump. We’re at 0 deg F this morning, and my Mr Cool Universal without heating strips doesn’t care. I felt I was paying too much for propane in my old shop. We heat the house partially with oil, but those burners require regular cleaning maintenance. It ***** that our electricity is currently about 34 cents/kw-hr, but the heat pump, like @danski0224 notes, uses only a fraction of the power of electric resistance. And you don’t need space for a tank, or to keep an eye on your fuel level. The heat pump uses an air handler that you could install cheap ductwork to distribute the air, and is much quieter than a hanging heater.

 

[PoorUB]

Take a hard look at a cold weather capable heat pump.

He will need a few of them! With decent insulation he needs around 100,000 BTU, maybe less because of the area, but then maybe more with "partially insulated".

We really need more info, and more insulation!

 

[Yankeefarmer]

He will need a few of them! With decent insulation he needs around 100,000 BTU, maybe less because of the area, but then maybe more with "partially insulated".

We really need more info, and more insulation!

Agree. With a combination of some partitioning and insulation he could get pretty close, especially since he says he’s only looking for a 20 degree rise. Isn’t your 30 btu/sq ft rule of thumb based on closer to a 60 degree rise?

 

[PoorUB]

Agree. With a combination of some partitioning and insulation he could get pretty close, especially since he says he’s only looking for a 20 degree rise. Isn’t your 30 btu/sq ft rule of thumb based on closer to a 60 degree rise?

Probably closer to 100 degree rise as here we need to heat at -40F once in a while, but I consider reasonable insulation and decent building practices. In this guy's situation with questionable insulation we might need to deal with huge heat loss so it might bring us back to 100,000 BTU.

If he wanted to go with heat pumps I might install a couple 36,000 BTU units, try it out and expect to install a third.

Also I would size the heating for right around 0F as it hits it there occasionally so it gets that BTU number back up there. Also, if you are going through the trouble to heat it, make it comfortable!

 

[pcmeiners]

"Building is 3000 sq ft with 16 ft side walls and a 26 ft peak."

For an 1100 10 ft ceiling, I have a 12000 heat pump. it was 7°F this morning in Bloomsburg Pa and the Fujitsu extra low temp, high efficiency unit intermittently went on an off, basically not even placing a load on it. If I placed it on "high" I could heat more then twice the space. It averages a COP of 4, which means for every 1000 watts, it produces 4000 watts of heat, 4 times as efficient as electric resistance heat, produces cooling with same efficiency.
Big concern for you is your high ceilings, and your insulation value at your ceiling level.

 

[Mr onetwo]

I have had a little experience with an air rotation system in an aircraft hanger parts facility situation and it was eye opening.These systems are amazing in your situation.Super efficient and you don't even know they are running.We found zero temperature stratification floor to ceiling. You can get an oil fired system and it would work fantastically. https://www.thermocycler.com/air_turnover_heating.htm another https://johnsonairrotation.com/johnsonairrotation/ If I remember correctly the unit was a Johnson...around 750,000 btu

 

[jblnut]

I second the wood stove and I'd use an 8-10" heavy wall pipe for a chimney. Wrap it with some regular ductwork and put a fan on the bottom to blow air past it with a couple ceiling fans to move it all around. Make sure to put a clean out at the bottom as you'll want to clean it at least annually.

I grew up with a triple 55gal barrel wood stove in a similar sized and insulated building in central MN and that thing would heat us out if we let it really cook. Gramps usually burned stuff that shouldn't have been burnt in the bottom barrel and had a wood fire in the middle barrel. The second barrel had pipes running through it with a big squirrel cage fan blowing through them. It didn't seem to matter what was being burnt in the bottom barrel and the smoke always came out nice and white-ish. Never a black puff from what I remember. I think the bottom barrel had an oil drip as well if I remember correctly. I wish I'd have taken pictures of it before we scraped it as it was definitely unique.

So. I vote wood stove. Doesn't matter how poorly insulated it is, you'll just need more heat. If you have wood you can just feed it more often until you insulate more ..... Or just keep feeding it lol

 

[Mr onetwo]

Check with your insurance company because a wood stove is illegal for use in a garage/shop in most states.You have a fire and you are SOL

 

[billconner]

Check with your insurance company because a wood stove is illegal for use in a garage/shop in most states.You have a fire and you are SOL

Is it illegal or uninsurable?

 

[gmcgeo]

Is it illegal or uninsurable?

uninsurable, not illegal

 

[billconner]

uninsurable, not illegal

That was my understanding. And I assume they'll take your money, but just won't pay a claim for loss resulting from wood burning appliance. Be interesting to learn if pellet, coal, and gas are also uninsurable.

If it's a "shop" instead of a "garage", I wonder if that changes it. Maybe time to call my insurance agent and ask.

 

[gmcgeo]

That was my understanding. And I assume they'll take your money, but just won't pay a claim for loss resulting from wood burning appliance. Be interesting to learn if pellet, coal, and gas are also uninsurable.

If it's a "shop" instead of a "garage", I wonder if that changes it. Maybe time to call my insurance agent and ask.

My Wifes company will Drop you, if you will not remove it.

 

[billconner]

My Wifes company will Drop you, if you will not remove it.

Yes, I'd guess if they knew it was there they would.

I wonder if stores that sell these are insurable? My brother's shop has many operating stoves and fire places in several buildings. Actually, old wiring caused a fire in one and I believe insurance covered it.

 

[gmcgeo]

Yes, I'd guess if they knew it was there they would.

I wonder if stores that sell these are insurable? My brother's shop has many operating stoves and fire places in several buildings. Actually, old wiring caused a fire in one and I believe insurance covered it.

Most insurance companies usually cover wood stoves or pellet stoves as long as you meet the conditions for coverage. These conditions vary according to the provider but typically include professional installation and a safety check by an official inspector.

 

[Mr onetwo]

straight from 2019 NFPA 211

13.2.3 Solid fuel–burning appliances shall not be installed in
any location where gasoline or any other flammable vapors or
gases are present.

13.2.4 Solid fuel–burning appliances shall not be installed in
any garage.

not my opinion....fact
install at your own peril

 

[billconner]

So the question is does your jurisdiction adopt that part of NFPA 211. New York State does not but separately prohibits wood stoves similar to 211. Pellet stoves appear to be allowed. I couldn't find out about coal. I'm assuming gas stoves are allowed but don't take my word for it.

NFPA codes and standards are not laws unless adopted by your jurisdiction.

 

[Mr onetwo]

That is true, but the great majority of states and localities have due to the influence of local fire departments.There is a requirement somewhere in the codes about distance above the floor, so stoves in general are problematic.

 

[billconner]

NFPA codes also require fire sprinklers in new one and two family dwellings. The IRC does also, but the majority of jurisdictions amend it out when adopting it into law. NFPA also requires maximum 7" risers and minimum 11" treads in home stairs, not the 7 3/4" and 10" of the IRC. Just saying what's published by NFPA or IRC or other standards developer organizations is just that, published, but not law.

Not taking any position, just trying to sort out what is law from what is good design and/or part of an agreement with an insurance company.

Not sure what code or standard requires elevating what, but the gas hot water heater generally no longer required to be raised.

And does this make sense in a garage with just EVs? I'm not sure it's even a danger in a modern garage used to just store modern vehicles. Gas tanks are a lot better designed and built today, and for a while, than 30 or 40 or more years ago.

 

[seavonj]

I think that the garage wood burning stove concerns are misplaced and misunderstood. Most of us have a propane water heater in the garage that could go up just as easily. It’s all in the proper installation of the wood burning stove. Follow the code, store flammables and fuel away from the stove and preferably in an outside shed and vented. I also pounded my head up against the wall on this subject and finally pulled the trigger and did it. I absolutely love the wood stove in the garage, it cuts the chill out, adds a nice touch to the garage and works great. Plenty of wood in my area and property to burn. You just have to be responsible and careful with it. I installed this one 18” above the floor just like the hot water heater code( I went above and beyond the stove code), all of the installation was done per code and per the manufacturers requirements. I also picked up this little Vermont castings Aspen 1920 for $75 and invested about $600 in parts to restore it. it was designed for a 800/1000 sqft space. Works flawlessly. Nothing like hanging out in thebgarage wrenching on bikes by the fire with a nice cup of coffee.

 

[drmarkr]

Pellet stove...have one in my shop and in our house.

 

[Jackfre]

Installing a wood stove or oil furnace will require a certified vent system. You can use L-vent rather than the 103HT type to help with cost. Pellet vent is L-vent. You would have to check Appendix E in NFPA 31 for sizing as PV is only offered up to 4” Dura-vent may have 5”.
In your situation given that you want to work there occasionally a wood stove will make you warm by the time you are ready to leave. I would suggest that you look at the Toyotomi direct vent kerosene heaters. They are very good, reliable, a simple install & efficient. I think their largest is 40kbtu. Your load will be substantially higher but the suggestions to petition and area, even with a curtain could help.

L-731/732 Toyotomi Vented Heater Now Available In White Or Graphite

L-731/732 Toyostove Laser Vented Heater

toyotomiusa.com

 

[Jackfre]

Who manufactures a 93% oil furnace. I have never heard of any thing over about 83%.

in ‘85 I represented Yukon in the New England States. They made the ULTIMA EX-95 condensing oil fired furnace. They vented with pvc. If ever a product called for dealer certification before sale this one was it. It was offered to general distribution, sold freely to the trade and ultimately put the company out of business. It was quite a story and quite an experience. One of the problems was that the unit needed to be precisely set up and serviced. There were few digital analyzers at that time fewer in use, so the meathead factor played into its demise. I think Thermopride is making one today.

 

[Fav Onefour]

Have a large metal building, partially insulated. Would like to make the space comfortable before next winter, and by comfortable, I mean tolerable enough to go out and work for a couple hours in the evenings. 45F inside when it is 25F outside would be nice. Building is 3000 sq ft with 16 ft side walls and a 26 ft peak. Would a circulation fan near the roof help more than I think it would? Does anyone have suggestions?

I hope it is ok to do a partial quote from the OP, who also has not responded after the first question in Feb.

We deal with temp heat quite often in farm sheds. I'm not quite sure if that is the object in this situation?

These little heaters make a lot of heat.

There are quite a few newer variations of this type on the market today. There are also quite a number of fuel options.
The simplicity is hard to beat. You need fuel and an outlet.
Most of the time, we turn them on only when we want heat. It's not a long term solution to heating a building, They aren't fancy, but the price is hard to beat.

Talk about the circulation fan question is pretty simple too. Take an IR heat gun and point it at the bottom of your roof. A fan will only move air. It will never make air warmer than that high point.

 

[pcmeiners]

Compare fuel costs.....

https://www.maine.gov/energy/sites/maine.gov.energy/files/inline-files/Home-Heating-Calculator.xls