Stove recommendations for small office shed with really tall ceiling

[smitten]

So we just built a 240 sq ft office but it ended up with two lofts and a really tall 14' ceiling. Wanting to heat it with wood. We are often running 20-40 degree days in the winter. Any recommendations on what type of stove to get? I'm seeing really good feedback on this forum on the Jotul. I saw a Jotul F500 on Craigslist that needs a replacement on the window and brick, but otherwise works great. Not sure if that'll be too big for the heating space though. Any experienced feedback? Wood stoves are new to my adulthood, although we used them when I was a kid.

 

[jetsam]

Any chance we can get a picture of what a 12x12x14 shed might look like?

Also need details on wall thickness, insulation type, windows, and general airtightness. Also whether it's on a slab or joists.

Many small shed type buildings used as shops need a big stove because they are poorly insulated and need to go from 20 to 40 quickly to make working in them tolerable without gloves. An office might have higher expectations as to temperature... so start by describing the outcome you want and what the insulation and window situation is!

For example, if you said it was not insulated and wouldn't be heated overnights, I'd point you at a big steel tube stove like a 32nc (which by the way is going to make you wish you had somewhere else to stand because it'll be 40 inside and your back will be 150 if you're next to it). If you said it was tightly and carefully insulated and needed to be 70 degrees 24 hours a day, I'd point you at a medium sized BK like the Princess.

In general a small space is challenging to heat because often it takes a lot to get it warm,, but after it's warm either you need a stove that turns way down, or a small stove that comes with a 4 hour burn time and its own special woodpiles full of weird little splits.

 

[smitten]

It's 12x20x14 with a barn-style roof. 2x4 construction. Still under construction, but will have 3" of R-Max rigid foam insulation in the ceiling (along with several radiant foil layers) and then covered with pine tongue and groove. The walls will have R-13 paper-backed fiberglass insulation with premium foil radiant barrier on the east/south/west walls.

It has an insulated floor on skids. Don't know what the builders put into the floor for insulation though.

We have several double-pane windows.

• 4'x6' (openable)
• 4'x6' (openable)
• 4'x5' (openable)
• 2'x2' (openable)
• 2'x2' (openable)
• 2'x3'
• 2'x3'
• 2'x3'
• 2'x3'

We'll want to maintain something around 68-74 degrees if possible. Don't mind a little extra heat. But don't want it much colder since the baby will be playing in the office too. The little kids will play in the loft that will be above the stove during the day. And the older kids will sleep in the other loft that will be above the desks at night, but it can be much cooler without issue for them at nighttime.

 

[jetsam]

Well, that should be a lot easier to heat than your average shed in spite of the tall ceiling. Insulation changes everything! Does it have double-pane windows?

Decide now where you want the stovepipe (a straight shot near the ridge beam on the side with no loft would probably be easiest).

If it's to be kept at 70 all the time and you want 100% wood heat, I'd pick an extremely controllable stove like a Blaze King. If you want to heat mostly or partially with wood, you could put in a minisplit and use a small stove to keep the electric from running when you are around to feed it.

If you put in a minisplit and leave the thermostat at 60 all winter, even a small stove won't take all day to get it up to 70.

That's also kind of an ideal use case for a masonry heater, but it's too late to go that route now.

 

[RockCastile]

My shed residence is the almost the same in dimension as yours, tho a tad shorter and a little less total window area, and similarly insulated. I heat it satisfyingly with a jotul 602, but a strong x2 on jetsam's mention that a space this small is generally tricky to heat with wood stove. In my Va. Blue Ridge climate, except for rare arctic blasts (low temps 0-5F) the stove cannot be run continuously without overheating the space (avg overnight lows here about low 20's F). Procedure for me is many, many fires, rarely if ever packing the stove full, burn times in the 2-3 hour range, and a woodpile composed primarily of medium BTU tree species. As for catalytic stove, athough the idea is mentioned here for tiny house heating, I've yet to see a post from someone who is actually using one successfully to heat such a tiny, decently insulated space. Perhaps its being done, perhaps by forum members, but I have yet to see their posts. Love my jotul, love wood-only heat for my space, don't love endless re-starts.

 

[stoveliker]

My shed residence is the almost the same in dimension as yours, tho a tad shorter and a little less total window area, and similarly insulated. I heat it satisfyingly with a jotul 602, but a strong x2 on jetsam's mention that a space this small is generally tricky to heat with wood stove. In my Va. Blue Ridge climate, except for rare arctic blasts (low temps 0-5F) the stove cannot be run continuously without overheating the space (avg overnight lows here about low 20's F). Procedure for me is many, many fires, rarely if ever packing the stove full, burn times in the 2-3 hour range, and a woodpile composed primarily of medium BTU tree species. As for catalytic stove, athough the idea is mentioned here for tiny house heating, I've yet to see a post from someone who is actually using one successfully to heat such a tiny, decently insulated space. Perhaps its being done, perhaps by forum members, but I have yet to see their posts. Love my jotul, love wood-only heat for my space, don't love endless re-starts.

The difference with a continuous home heating and an intermittent use space as here, is that the stove needs to be able to put out much heat to heat up the place, and then little heat to maintain. So the dial down ratio is important: given max BTU output, how little can you put out in a stable manner.

That is where a Tstat controlled cat stove does well. Hence the BK suggestion.

 

[mar13]

A mini-split as a 2nd (and more on-demand/simple) option for heating, in addition to a woodstove, would also provide air conditioning in the summer, I believe.

 

[smitten]

Because of electrical sensitivities, we want only wood heat. No electrical.

 

[smitten]

Yes, it has double-pane windows!

We're thinking to put the stove in the front left corner with the stovepipe going up through the loft, since the space above the middle windows will be for the ladder

 

[smitten]

My shed residence is the almost the same in dimension as yours, tho a tad shorter and a little less total window area, and similarly insulated. I heat it satisfyingly with a jotul 602, but a strong x2 on jetsam's mention that a space this small is generally tricky to heat with wood stove. In my Va. Blue Ridge climate, except for rare arctic blasts (low temps 0-5F) the stove cannot be run continuously without overheating the space (avg overnight lows here about low 20's F). Procedure for me is many, many fires, rarely if ever packing the stove full, burn times in the 2-3 hour range, and a woodpile composed primarily of medium BTU tree species. As for catalytic stove, athough the idea is mentioned here for tiny house heating, I've yet to see a post from someone who is actually using one successfully to heat such a tiny, decently insulated space. Perhaps its being done, perhaps by forum members, but I have yet to see their posts. Love my jotul, love wood-only heat for my space, don't love endless re-starts.

Good to know! That many restarts sounds like a lot! We have lots of juniper and pine around here for burning purposes. Would that work?

 

[smitten]

Well, that should be a lot easier to heat than your average shed in spite of the tall ceiling. Insulation changes everything! Does it have double-pane windows?

Decide now where you want the stovepipe (a straight shot near the ridge beam on the side with no loft would probably be easiest).

If it's to be kept at 70 all the time and you want 100% wood heat, I'd pick an extremely controllable stove like a Blaze King. If you want to heat mostly or partially with wood, you could put in a minisplit and use a small stove to keep the electric from running when you are around to feed it.

If you put in a minisplit and leave the thermostat at 60 all winter, even a small stove won't take all day to get it up to 70.

That's also kind of an ideal use case for a masonry heater, but it's too late to go that route now.

Yep, windows are double-paned. And we're gonna have to put the stove in the front-left corner of the building since we need the other space you suggested another loft and/or stairs.

I saw a Blaze King on Craigslist or somewhere. It looked like it'd been spray painted, but they said it worked well. Since I do need to go with 100% wood heat, any pointers on finding a good used one? Or any thoughts on what size of one to get?

 

[Hoytman]

Jotul 500, NC 30, BK????
All those are way too big for that space. Not even close to realistic especially with insulation.

You have to remember what sort of temperatures you need coming off of a stove or this size in a large home just to keep your stove and chimney clean. Those same temps are needed for the stove and chimney even though the space being heated is waaaay smaller...which means such a big stove is going to be throwing a tremendous amount of heat with even the smallest of the stoves so far mentioned. Even with the smallest BK stove burning on low the stove tops are still huge and giving off a ton of heat for such a small space, even burning on low. I not only think the suggestions are off, but way off if you only want heat during the day and even if you heat 24/7. A much smaller stove is still quite capable of warming things up inside and then burning low while the space is occupied.

I would say something like a small Jotul or Morso Squirrel stove would be a better option and even they are still a tad too big for the space you are looking to heat and it still way smaller than any of the big stoves mentioned in other posts. https://morsoe.com/us/product/indoor/wood-burning-stove/p1410_us#m-technical-data

This might serve you better. Make no mistake, this little beast can still throw a ton of heat. https://smallwoodstoves.com/default/tiny-salamander-wood-stove/salamander-tiny-stove-us.html

I personally like these for spaces such as yours. In fact, I am considering one similar to this https://www.tinywoodstove.com/product/small-stove-the-dwarf-5kw/ in my shed which is bigger than your space, un-insulated and 4” block. If I need to insulate later depending on the time I spend in the shop, then I will do it.

Don’t under estimate the ability of a small stove nor the ability of a hot wood fire from a small cast iron stove. Just don’t over-fire the stove when first heating the space. Give it time to do it’s job and in a few minutes you’ll be turning the stove down.

You do not need even a small stove by any major stove manufacturers as they are still too big. Look more closely at these tiny stoves and if you really think you need a bigger stove than those, then still do not go any larger than the Morso Squirrel. The Jotul 602 might be rated for a little bigger space than the Squirrel, but I can’t be certain without looking it up for you.

I could heat my entire 1350 sq ft insulated home with a Blaze King Princess burning on low even in the coldest weather. That stove is wayyyyyy too big for a small insulated shed.

 

[jetsam]

I'd burn a BK in that space, but it may not be a good choice for a novice burner. It is the only option that offers 24 hour low heat, but I worry that a new burner is going to have wet wood, not know how to tell if the cat is burning or not, and end up with a serious creosote problem.

I guess I am going to suggest hot little fires in a small stove (aggravating as that is) unless you are really willing to commit to learning a lot of nitty gritty details about stove operation and chimney sweeping- because an EPA BK does have wonderful low heat output, but it will also happily smolder entire loads to death if the operator lets the cat drop out.

 

[Hoytman]

I'd burn a BK in that space, but it may not be a good choice for a novice burner. It is the only option that offers 24 hour low heat, but I worry that a new burner is going to have wet wood, not know how to tell if the cat is burning or not, and end up with a serious creosote problem.

I guess I am going to suggest hot little fires in a small stove (aggravating as that is) unless you are really willing to commit to learning a lot of nitty gritty details about stove operation and chimney sweeping- because an EPA BK does have wonderful low heat output, but it will also happily smolder entire loads to death if the operator lets the cat drop out.

I totally get the suggestion of a BK for the use of the thermostat. My coal stove has a thermostat ... it is large enough to heat 3000 sq ft, but the beauty of coal is I can burn it low enough to do this...
...and I can hold my hand on that pipe as long as I want to. See that pipe temp? I can hold draft with the IR gun reading 85F...that’s about 160F internal temperature. The back stove wall under the thermostat is 175ish degrees...and that large stove is still throwing a lot of heat into my 1350 sq ft home and holding indoor temps at 72F even with outdoor temps in the 40’s. This home was built in 1954 and nowhere near insulated as well as that shed will be.

This is why there is now way, even heating 24/7, that I’d recommend anything larger than. Morso Squirrel or Jotul 602. As I’ve said, even those are likely still too big. Even the small SBI stoves, brands like Osburn and Drolet have stoves that turn down as low as 500sq ft and will still heat 1800 sq ft... still way too big...which spell me out creosote problems in the stove and the chimney pipe. Go smaller stove like the tiny stove and burn them hot and clean and even a low burn will be hot enough to keep the chimney clean yet small enough to not be too hot and have enough size for additional heat if needed.

I mean, you can go with a much bigger stove like. BK Princess and try it, but I think you’ll be down to your panties in front of the kids.

 

[smitten]

I totally get the suggestion of a BK for the use of the thermostat. My coal stove has a thermostat ... it is large enough to heat 3000 sq ft, but the beauty of coal is I can burn it low enough to do this... View attachment 275674View attachment 275675View attachment 275676
...and I can hold my hand on that pipe as long as I want to. See that pipe temp? I can hold draft with the IR gun reading 85F...that’s about 160F internal temperature. The back stove wall under the thermostat is 175ish degrees...and that large stove is still throwing a lot of heat into my 1350 sq ft home and holding indoor temps at 72F even with outdoor temps in the 40’s. This home was built in 1954 and nowhere near insulated as well as that shed will be.

This is why there is now way, even heating 24/7, that I’d recommend anything larger than. Morso Squirrel or Jotul 602. As I’ve said, even those are likely still too big. Even the small SBI stoves, brands like Osburn and Drolet have stoves that turn down as low as 500sq ft and will still heat 1800 sq ft... still way too big...which spell me out creosote problems in the stove and the chimney pipe. Go smaller stove like the tiny stove and burn them hot and clean and even a low burn will be hot enough to keep the chimney clean yet small enough to not be too hot and have enough size for additional heat if needed.

I mean, you can go with a much bigger stove like. BK Princess and try it, but I think you’ll be down to your panties in front of the kids.

Impressive! And how long can I expect to go between adding more wood or making a whole new fire in one of these little stoves?

 

[Hoytman]

Impressive! And how long can I expect to go between adding more wood or making a whole new fire in one of these little stoves?

That is the issue you have with that small of a space. The answer is; not long in most of those stoves. The bigger stove you have the longer it will burn, but it’s all trade-offs. You will have lots of heat cycles with the tiniest of stoves, and less as the stoves get bigger. Probably why the BK and thermostat was mentioned.

I didn’t mean for my post to sound like the other posters suggestion was totally wrong, but it would be an expensive mistake if it was, and I believe it is. Those BK stoves are great, but also $3000.00 to $4000.00 depending which model and where you buy them...and to have one be too big for heating the space, not to mention physically taking up too much space in your small space, then it would only be a major disappointment.

Here is yet another option that is still likely way to big for you, but I’ll leave that up to you. To be sure, I personally feel this option is also too big...
https://store.woodstove.com/product.php?productid=16798&cat=248&page=1 ...
but I will say this about it... if it can be purchased with soapstones inside the fire box, then it is quite possible you could have one or two small fires a day, let the stove go completely out, and still have enough heat in the stones to keep comfortable.
The benefit to this option is this....it is a catalyst stove like the BK but no thermostat unfortunately. The plus side is a small piece or two of wood 12” long on a bed of hot coals could, engaging the catalyst, provide for a super clean and safe burn, and extended burn time for same size of wood in another small stove. Here is a review you can read for your own research. NOTE: The space being heated is still much larger than yours and so I believe this unit to still be too big for your space. The final choice is up to you. All I can try and do is provide good information. https://firewoodhoardersclub.com/forums/threads/woodstock-stove-survival-hybrid.33726/

This stove is rated for up to 1000sq ft. However, it will hold heat with soapstone liners IF it can be ordered with them. I am unsure about that.

I still recommend, for that insulated small space, at least looking into the smaller stoves I linked to. Also, go ahead and check on the BK stoves. Maybe they have a small stove I am not aware of, but the Princess, although would be great if it would work, I am afraid is still much too large. Too much heat taking up to much space that you need.

From the other links to tiny stoves I provided, including the Morso Squirrel and Jotul 603, do your research by calling them or asking users here how long their burn times are. Don’t take a brochures word for it, ask around, ask dealers, then ask users. Be vigilant and persistent in your research, and most of make good decisions based on your needs from the information you gather.

 

[RockCastile]

The previous model Jotul 602 had a burn time of 4 hrs. (Dont know deets of new 2020 model, V2). I dont pack mine full when I start a new fire, and I usually am down to coals ready for reload in about an hour. If it's pretty chilly out I can do a 2nd and occassionally 3rd reload before the room temp hits time-to-stop-or-open-the-windows. By the time the room feels like it could take heat again, my coals are gone....restart in a few hours or wait til evening. I've seen posts from wizards on here who have figured out how to get overnight burns with the 602, I accidently did it myself one time with a big piece of dry locust, but have no idea how it happened and cannot repeat it if trying.

 

[Hoytman]

The previous model Jotul 602 had a burn time of 4 hrs. (Dont know deets of new 2020 model, V2). I dont pack mine full when I start a new fire, and I usually am down to coals ready for reload in about an hour. If it's pretty chilly out I can do a 2nd and occassionally 3rd reload before the room temp hits time-to-stop-or-open-the-windows. By the time the room feels like it could take heat again, my coals are gone....restart in a few hours or wait til evening. I've seen posts from wizards on here who have figured out how to get overnight burns with the 602, I accidently did it myself one time with a big piece of dry locust, but have no idea how it happened and cannot repeat it if trying.

Good post.

I keep forgetting the space the person is wanting to heat is 14 ft high. That said, a ceiling fan will be needed to move heat back down into the space. This is a must.
Also, with the higher ceiling you just might get by with a 602 or Morso Squirrel or equivalent sized stove...but I’m still in the edge. The positive side to these recommendations, or even the WoodStock Survival Hybrid I mentioned, is that you don’t have to load this full with a big load of wood. The flip side of that is, might as well look into the even smaller stoves then and expect lots of loading. Either way, you’re going to be constantly loading a stove.

Now, if anthracite coal fuel was something you would consider burning, then I can greatly increase your constant, reliable, and steady heat output, less loading, and zero chances of a chimney fire. Then I could point you to other quality stoves that are small and could still burn wood in a pinch. However, I won’t mention these until you ask.

240 square feet and keeping it heated without many and even major heat swings is near impossible without lots of stove tending and re-loading. Might as well just plan on lots of stove tending, but it shouldn’t be too bad being you are insulating well. Burning anthracite coal or wood pellets are the only options to less tending, that I am aware of except for a masonry heater and your space is already much too small for that.

 

[Hoytman]

You also have the options of these gas stoves on this site https://store.woodstove.com/ and hooking them up to a propane cylinder outside of the shed. Personally, one of these, along with a couple good CO detecters, might even be a better option yet for you. No loading of wood or removing ash and no mess, and fits into a small space.

 

[Hoytman]

Oh...when I mentioned my coal stove I forgot to mention why I brought it up.

Wood varies a lot in btu’s per pound of wood with different species of wood. A good number to figure would be about 8600 btu’s per pound. Depending on wood species this can be more or less. Others here can go into wood btu’s better than I can, but...

...I will tell you about my coal stove and how much coal I am using.

Anthracite coal has about 12,500 btu’s per pound. Lots more btu’s per pound of fuel compared to wood.

Today I sat down and figured up my coal usage per hour burned over the last 57 days. I came up with a total of 1.03 lbs of coal burned per hour....every hour for the last 57 days. That not much fuel usage at all.

So to make it easy to under stand, my home of 1350sq ft has been using only 24 lbs of coal per day for the last 57 days. I tend twice a day and that is it. So it takes only 12,500 btu’s per hour to keep this not so well insulated home heated to a comfortable indoor temperature of 72F average.

In other words, your much more tiny space will require nowhere near 12,500 btu’s per hour and is precisely why I mentioned and linked to those much more tiny stoves.

Even if a larger wood stove can burn that low, down to the same 12,500 btu’s per hour, remember that at their rating you will be burning nearly two pounds of wood compared to one pound of anthracite coal....which means lots more tending with wood.

The flip side for me and my stove is I wanted to buy a wood/coal stove so I could also burn wood in it. However, I have discovered that in order to maintain a creosote free stove and chimney for such a big stove I will have to burn the stove much to hot for my homes space which means there is no way possible that I could rest my hand on my stove pipe like I can with coal. It’s impossible with this stove and my home temps would be so high I’d have to open windows and waste fuel.

So do your research, ask questions, and choose the correct size stove. With coal, stove size isn’t as important because it can be burned so low. The only thing close is. Blaze King stove that was mentioned. But keep this in mind, there is a vast difference in size between a tiny stove and even the smallest BK wood stove and the larger at 400F will give off waaaaayyyyy more heat than the tiny stove at the same 400F temperature.

Even with wood and in a normal home you have some leeway with regard to stove size. However, the smaller the space, the more closely the stove needs to come to be correct size for the heating requirements. It’s down right critical the smaller the space to be heated.

 

[Easy Livin’ 3000]

I'm going to throw in the idea of some sort of masonry heat sink, if a wood stove is going to be used. Not as good as a masonry heater, but a heavy pile of rocks and/or concrete around a the stove to soak up some heat and radiate it back into the space would be helpful.

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[stoveliker]

I'm sorry, but the Morso squirrel is rated for an output of 5 kW. That equates to 17,000 BTU per hour.

A BK Sirocco 20; firebox gets 11,342 BTU per hour. For 20 hrs.

The Morso's data are not as illuminating as the BK, so maybe there is more to it.

What you could do is to get a calculation of the BTU need you have with that build, climate, and use. As minisplits seem an option, and good hvac dealers do such a calculation, I suggest to engage one or two and get some data. That'll allow you to compare different kinds of stoves (and other systems) based on proper data.

 

[stoveliker]

Here

The Morso Squirrel Wood Burning Stove Review

In total, there are 8 different Morso squirrel stoves available, the most popular being the Morso Squirrel 1410 & 1412. Read the full review of each stove here.

www.stovesupermarket.co.uk

.

I understand this thing can go down to 4.5 kW, "making it suitable for small spaces", suggesting this is the output range on low.
4.5 kW is 15,300 BTU/hr.

 

[RockCastile]

We have lots of juniper and pine around here for burning purposes. Would that work?
[/QUOTE]

I use pine to good effect in my 602, as with all wood make sure you can get it dry and keep it dry before using. Oft-repeated advice is to avoid pine due to creosote, but if its truly dry (below 20% moisture) it's no more of an issue than other species. Also, if you can come by it, wouldn't hurt to have at least a portion of mid-range BTU species in your woodpile (not familiar with common trees where you are). Adding a couple-three sticks of that to the pine or spruce will give your fires a little staying power. If you make sure the chimney system is done right for proper draft and stay on your game vis a vis keeping dry wood, the re-start process gets a whole lot quicker and easier.

 

[stoveliker]

Of course btu output in a squirrel can be decreased by small and intermittent fires. The BK does not do that (well).