Stove sizing

[Gorben82]

Hello,

I am building a cabin in WV appalachia. The cabin is 16x24 (380 sqft) with 9/12 roof pitch and vaulted ceiling around 15ft at peak and a loft (16x10 away from stove). Insulation is r13 all around and r10 on the floor. This is a week end cabin, I am expecting a lot of cold starts in the 30s.

My wife does not deal well with cold temperature and if I am unable to warm the place in a reasonable amount of time, this will be a deal breaker. I never really had a wood stove before so I am not sure what to expect.

I like the drolet nano/1200. Price point would work well but I am unsure if it will be big enough. Would a cast iron stove like the jotul F 602 be better? Drolet also has a 1800 that seems quite a bit bigger than the 1200. Would that be better? My goal would be to make the place confortable (60+) within the hour. Ideally I would like to keep the stove <$1500.

Thanks for your help!

 

[begreen]

The goal is somewhat unrealistic unless the cabin has been kept at 50º or so while empty. It's good to think larger for the stove. It takes a lot of extra BTUs to bring up not only the room temp, but also to heat up the mass of the building and its contents. A wood stove could take 3-6 hrs to do this. The first 30 minutes is just warming up the stove enough to radiate heat. Another issue is feeding cycles. A small firebox is going to need to be re-fed every 2-3 hrs when pushed for heat. This is where a larger firebox helps. However, once the place has warmed up there is a possibility of overshoot and the place getting too hot due to the small space being heated. The typical remedy is to open a door or window, but that may not satisfy her.

The best compromise is to have an auxiliary source of heat for the quick blast but one that can be shut off quickly. Electric or propane heaters can do this in conjunction with a smaller stove. Otherwise, get a stove in the ~2 cu ft range. The True North TN20 is worth considering. It heats up quickly and loads N/S for full capacity loading.

FWIW, my wife is a trooper, but does not deal with the cold either. Regardless of choice, be sure to invest in an electric blanket so that the bed is fully warmed up.

 

[Gorben82]

Oh wow, thanks for your reply. I did not realize that it would take so long. I like the idea of a heating blanket. That would definitely help.

When you say 3-6 hrs, is it with the drolet nano/1200 with 45000 BTU or the 1800 with 70000 BTU?

 

[EatenByLimestone]

Ok, I have a cabin that’s a similar size to yours. 16x29. I frequently come up in winter and heat the cabin from 10F, sometimes in the negatives, etc. I have a 2cu ft stove. It has a steel box, and cast iron surround to dull the searing heat that can come out of it. After the heat up, it’s tough to keep the place from being a sweatbox if it’s not under 30. Don’t rely on the stove alone if you want a happy wife.

So, if you’re not going to be much under 30 as an outside temperature , I’d stay smaller than 2 cu ft.

I use multiple heaters to warm my place up. When I walk into a cold cabin I plug in some electric heaters, I have every outlet on its own circuit so I can run a number of them if need be, and I turn on a propane sunflower heater that runs on a 20lb propane tank. I think they put out 15k btu. In a pinch, I’ve also fired up the propane cooking stove. Each burner adds to the heat. It takes a lot of energy to warm a cold structure in a relatively fast time.

A word of warning with the ventless propane. It puts a lot of water into the air. If it’s real cold, that water will condense on the walls. I don’t think it’ll happen at 30, but it does at -20, lol. Be aware you’re not exhausting combustion products outside too. It all stays in there with you.

 

[EatenByLimestone]

Oh wow, thanks for your reply. I did not realize that it would take so long. I like the idea of a heating blanket. That would definitely help.

When you say 3-6 hrs, is it with the drolet nano/1200 with 45000 BTU or the 1800 with 70000 BTU?

The more steel you have to warm up to temperature, the longer it’ll take before it starts pumping heat into the room.

The kicker to that is the smaller the stove is, the more often you have to load it while you want to sleep.

 

[begreen]

When you say 3-6 hrs, is it with the drolet nano/1200 with 45000 BTU or the 1800 with 70000 BTU?

I was thinking with the larger stove working solo to heat up the place. After an hour, you wife may be convinced to come out of the car but it may take another 2 hrs. before she takes off her parka. At that point, the air will be warmed up, but if you sit on a sofa it may still feel cold. That's what I mean by heating up the mass of the place.

A radiant stove with no shielding will heat up adjacent surfaces faster, but a convective stove like EBL has will be more comfortable once the place has warmed up.

 

[Gorben82]

Awesome, thanks a lot. That's exactly what I wanted to know! I want to be able to go there when it's really cold, but realistically it does not get THAT cold where I am. Looking at the monthly average in January, daytime is in the 40s and night in the 20s. I want to size the stove properly so we can still use it in the shoulder months when we only need a quick fire at night.

Having multiple source of heat makes sense. I can get the drolet spark II and a 80000 BTU convection LP heater for when we arrive.

I see that the small drolet as a maximum burn time of 5 hrs.... I guess I'll have to also invest in a good comforter .

I was thinking of installing the stove with a fresh air intake. I can see the benefit for the when the stove is going strong, but when it dies out... wouldn't the cold air from outside speed up the chilling process? Can I install a damper on the fresh air intake to block air coming in at night?

 

[EatenByLimestone]

In 40 degree temps, even 30 degree temps, I’m more likely to just run an electric space heater than start the stove. Your small stove and higher ceilings will change that equation quite a bit, but 40s aren’t all that uncomfortable. It’s hoodie weather.

 

[kborndale]

In 40 degree temps, even 30 degree temps, I’m more likely to just run an electric space heater than start the stove. Your small stove and higher ceilings will change that equation quite a bit, but 40s aren’t all that uncomfortable. It’s hoodie weather.

Takes a long time to warm up a cold cabin with space heaters, this isn't for a house that is already warm, it's for a cabin that's going to be cold when they arrive.

 

[EatenByLimestone]

Right. This is what I do for my cabin in the Adirondacks .

Once heated up, my stove will push you out of the room above 30 or so. You need lots of energy to warm the place up, but once there it doesn’t take much.

I should also note that I have extra 2”thick firebrick on the floor of my firebox to allow me to run smaller fires with a clean burn.

 

[kborndale]

I know the OP was not trying to spend a lot of money but this situation is perfect for a cat stove. You can get a large enough one to really crank up the heat when it's needed upon arrival, but can then cruise along low and slow once the place is heated up.

 

[Gorben82]

In 40 degree temps, even 30 degree temps, I’m more likely to just run an electric space heater than start the stove. Your small stove and higher ceilings will change that equation quite a bit, but 40s aren’t all that uncomfortable. It’s hoodie weather.

The cabin is off the grid so the electric heaters are probably not going to cut it. I can and will definitely get some LP heaters

Right. This is what I do for my cabin in the Adirondacks .

Once heated up, my stove will push you out of the room above 30 or so. You need lots of energy to warm the place up, but once there it doesn’t take much.

I should also note that I have extra 2”thick firebrick on the floor of my firebox to allow me to run smaller fires with a clean burn.

That’s exactly what I was afraid of. From all the calculation I made, it looks like I can maintain the temperature with 10k to 15k BTU. My main concern is to warm the place up rapidly.

I know the OP was not trying to spend a lot of money but this situation is perfect for a cat stove. You can get a large enough one to really crank up the heat when it's needed upon arrival, but can then cruise along low and slow once the place is heated up.

Thanks, I looked into those. The price point is certainly higher than I would like. There is also the catalyst that bothers me. I have been focusing on building the cabin so the wood that I have is still the trees that were cleared by bulldozer 18 months ago. They have been sitting on the side uncut and unsplitted. I am not sure how dry they are. I don’t want to ruin the stove.

Thanks for your help!

 

[kborndale]

The cabin is off the grid so the electric heaters are probably not going to cut it. I can and will definitely get some LP heaters

That’s exactly what I was afraid of. From all the calculation I made, it looks like I can maintain the temperature with 10k to 15k BTU. My main concern is to warm the place up rapidly.

Thanks, I looked into those. The price point is certainly higher than I would like. There is also the catalyst that bothers me. I have been focusing on building the cabin so the wood that I have is still the trees that were cleared by bulldozer 18 months ago. They have been sitting on the side uncut and unsplitted. I am not sure how dry they are. I don’t want to ruin the stove.

Thanks for your help!

Dry wood is just as important in non cat stoves. With any modern stoves you will be extremely disappointed trying to burn wood that isn't ready. Split that wood today and it may be ready for next winter, it's too late for this winter.