Using wood as a sole heat source, without backup systems?

[Rose Lane]

I’m interested in hearing from others who are using wood as a sole heat source- that means no backup propane, no backup electric- no backup, period.

1. What is the building spec?
2. What are the stove(s) you are using?
3. Do you have plumbing and what do you do to manage temp stability?
4. What is a typical overnight burn experience in zero or subzero temps?
5. How much wood do you use in a day or a year?
6. What is the daily temperature variance you experience in the building during zero/subzero temps?
7. Do you measure the moisture content of your wood?

I’ll post my own responses in a bit, as we are doing this both at home and workspaces. This post is inspired by a challenging off grid workshop situation described here, and the urge to design the perfect off-grid situation:

New Lopi Answer- Questions

This June 2021 manufacture Lopi Answer is the only heat source in this 350' off grid workshop. I'm having problems getting the fire burning on a daily basis and if the space was unused prior day, (and thus cold) it can take 6 hours to get the space up to a reasonable low 60s working temp. We...

www.hearth.com

 

[kborndale]

I would never go without some backup. Injuries is one worry, what if you become physically incapable of humping wood to the stove. Another issue is you can't leave the house alone for longer than 18 or so hours in the winter. When I am home my furnace rarely kicks on but I like to go away for the weekend, how do I do that without backup heat?

 

[Dan Freeman]

As kborndale said, and what if something happens to your stove and you can't use it for a while because you are waiting for parts?

 

[BIGChrisNH]

I’m interested in hearing from others who are using wood as a sole heat source- that means no backup propane, no backup electric- no backup, period.

1. What is the building spec?
2. What are the stove(s) you are using?
3. Do you have plumbing and what do you do to manage temp stability?
4. What is a typical overnight burn experience in zero or subzero temps?
5. How much wood do you use in a day or a year?
6. What is the daily temperature variance you experience in the building during zero/subzero temps?
7. Do you measure the moisture content of your wood?

I’ll post my own responses in a bit, as we are doing this both at home and workspaces. This post is inspired by a challenging off grid workshop situation described here, and the urge to design the perfect off-grid situation:

New Lopi Answer- Questions

This June 2021 manufacture Lopi Answer is the only heat source in this 350' off grid workshop. I'm having problems getting the fire burning on a daily basis and if the space was unused prior day, (and thus cold) it can take 6 hours to get the space up to a reasonable low 60s working temp. We...

www.hearth.com

I use wood as my primary heat source, but as others have said, I do have a back-up, an oil fired boiler in my case. Some information that may be helpful to you: I live in a 2200 square foot house heated by a Englander NC30. The NC30 will heat the house just fine down to temps in the teens. If temps stay in the teens for days at a time that is the upper limit of heating capacity for my situation, and the upstairs will get cold unless I turn on the forced hot water (baseboards). My wood usage is 4-6 cords per winter. I'm home all the time now, (remote job) so the temp swings are not what they used to be, pretty stable actually on 3-4 fires per day depending on weather. I also would have concerns about wood heat with no backup, if I was doing that I would give serious consideration to buying two stoves, and keeping one as a backup in case something were to break, and stocking up on spare parts. Hope this is helpful to you.

 

[begreen]

I would add:
8) What climate zone or state are you in?
9) How frequently do you reload the stove at:

a) 40ºF​

b) 20ºF​

c) 0ºF​

d) -20ºF​

10) Are you burning mostly softwood or hardwood?

 

[john26]

I had a great aunt and uncle that used a woodstove in the living room as primary heat source and back up was a second stove on the back porch open to the house. They did this up until 20 years ago.

 

[Dan Freeman]

I had a great aunt and uncle that used a woodstove in the living room as primary heat source and back up was a second stove on the back porch open to the house. They did this up until 20 years ago.

I guess at one time folks did that. I remember visiting my grandparent's farm as a kid back in the early 60's. They had 2 or 3 potbelly stoves. I guess if one went down, they had the other two, but those old potbelly's were built to last.

 

[Highbeam]

I think your question wasn't meant to exclude people that have a backup but rather to exclude part time burners that use their backup heat source as well as wood. I provide 100% of my heat from a woodstove. We of course have emergency backup wall heaters that haven't been used for heat since we bought the home 16 years ago. I think I fit into the response you were hoping for.

1. What is the building spec?
1700 SF single story built in 1963. Mostly vented crawlspace, some slab, 2x4 construction.

2. What are the stove(s) you are using?
Blaze king princess installed in 2012. Previously a hearthstone heritage. Previous to that a Lopi freedom bay insert.

3. Do you have plumbing and what do you do to manage temp stability?
Of course we have plumbing and we keep the house warm enough to prevent freezing. We don't vacation in the winter.

4. What is a typical overnight burn experience in zero or subzero temps?
We annually get into the single digits overnight for a few days and several spells in the teens, burn experience is great just increase the burn rate to match the greater heat loss. In the cold we reload every 12 hours instead of every 24.

5. How much wood do you use in a day or a year?
4 cords in the house stove, another cord or so in the shop. All low btu PNW species and currently 100% softwood.

6. What is the daily temperature variance you experience in the building during zero/subzero temps?
None. The stove puts out steady heat continuously via thermostatic control so the stove room stays warm. What changes in extreme cold is that the far bedrooms cool a bit more than usual relative to the stove room. So rather than a 2 degree difference throughout the home, it's a 6 degree difference.

7. Do you measure the moisture content of your wood?
I have two meters and occasionally check for fun and validation that the routine is working. When you get serious about wood heat you will develop a routine that works to produce excellent fuel dependably.

 

[bholler]

We have a fair number of customers with no backup at all. My father only has wood as well.

 

[Zzyk]

No backup. Two wood stoves for a 3000 sq ft farmhouse from the 1870's. PE Summit and Quad fire 4300. Last couple of weeks backup consists of not sleeping much. One spot where the pipes will freeze at a point so I will crack the faucets a bit. When we can afford it a backup will be added just not sure what.

 

[Todd]

I’m interested in hearing from others who are using wood as a sole heat source- that means no backup propane, no backup electric- no backup, period.

1. What is the building spec?
2. What are the stove(s) you are using?
3. Do you have plumbing and what do you do to manage temp stability?
4. What is a typical overnight burn experience in zero or subzero temps?
5. How much wood do you use in a day or a year?
6. What is the daily temperature variance you experience in the building during zero/subzero temps?
7. Do you measure the moisture content of your wood?

I’ll post my own responses in a bit, as we are doing this both at home and workspaces. This post is inspired by a challenging off grid workshop situation described here, and the urge to design the perfect off-grid situation:

New Lopi Answer- Questions

This June 2021 manufacture Lopi Answer is the only heat source in this 350' off grid workshop. I'm having problems getting the fire burning on a daily basis and if the space was unused prior day, (and thus cold) it can take 6 hours to get the space up to a reasonable low 60s working temp. We...

www.hearth.com

My first Winter off grid in my 800sq ft log cabin was just wood heat with a Jotul 602 CB but I did cheat on some weekends when I left to go visit family on weekends. During those times I used a Mr Heater space heater to keep the cabin warm while away. Now I have a larger Jotul F45 for longer burns and a propane wall furnace I use when I’m away.

I typically go through 3.5 cords per year mostly burning Aspen now and load the stove 2-5 times per day depending on the weather. Coldest temps in the cabin are early morning when it can get down to low 60’s when it’s below zero outside but I usually don’t reload in the middle of the night. Otherwise I keep the cabin 75ish during the day give or take a few degrees.

Also my only plumbing consists of a water tank in basement with an on demand pump and water heater plumbed up to kitchen sink. basement never gets below 45, usually stays around 50. Have composting toilet, outhouse and separate bath house sauna where well water is plumbed.

 

[Max W]

I can answer some of those questions with an eye to the past. So this is not based on my current situation but a house we built some years ago. We were off grid for the first year with propane lights an a hand pump.

1. What is the building spec?
The house was square, 2048 ft2, half height foundation framed above, family, sleeping and utility room down, kitchen and open living space above. Typical insulation for the 70’s, R11 walls, R19 ceiling, south facing windows .

2. What are the stove(s) you are using?
We put in an old, large, round, but not deep, tall cast iron, all gravity wood furnace with a huge plenum and small Atlantic cookstove upstairs.

3. Do you have plumbing and what do you do to manage temp stability?
Except for drain piping all the plumbing was concentrated in, above, or nearly above the utility / furnace room including the pipe from the shallow well and the pump. We had a claw foot tub with a heating duct directly beneath it. We liked to think it added a bit more warmth to the bath. We also put in a 220V built in heater in the bathroom. This was the only outside heat source in our 11 years there. Never had a frozen pipe.

4. What is a typical overnight burn experience in zero or subzero temps?
On the very cold nights we would load up the furnace. I liked to to have some rounds that I trimmed to squares for better fit. We sometimes got temps in the -30s.

5. How much wood do you use in a day or a year?
A lot

6. What is the daily temperature variance you experience in the building during zero/subzero temps?
I don’t remember having an indoor thermometer but we were very comfortable.

7. Do you measure the moisture content of your wood?
For our first year we measured it by how little or much it hissed.

8. We were in zone 4 then.

10. We burned all hardwood.

 

[electrathon]

I am guessing you would have difficulty affording insurance with wood only heat.

 

[bholler]

I am guessing you would have difficulty affording insurance with wood only heat.

It isn't a matter of cost at all here. Just finding the right company that will write a policy

 

[WoodGirl]

I would never go without some backup. Injuries is one worry, what if you become physically incapable of humping wood to the stove. Another issue is you can't leave the house alone for longer than 18 or so hours in the winter. When I am home my furnace rarely kicks on but I like to go away for the weekend, how do I do that without backup heat?

For most, the main issue is freezing water pipes. In that case, you have to drain the lines and then you blow compress air through the lines to make sure the pipes are mostly empty; a slight amount is OK as it would have room to expand.

 

[peakbagger]

BTW, Folks forget the alternative, Passive houses have zero heating system or backup. There are several Passive House builders in Maine. There is firm that prefabs then in Stetson Maine. The big trade off the cost is quite steep, the amount of extra cost to build the place to Passive House standards on a square foot basis would pay for lot of firewood for the life of the house.

"Russian Fireplaces" (actually masonry heaters) were quite popular in Maine 30 years ago, there was a "guru" in central Maine that built a lot of them and trained others to build them. Built right they can give off usable heat for 3 to 4 days. The trade off is they take quite awhile to warm up when the get cold. There really had been no successful method of thermal storage for long term periods. The big concept was rock beds, Maine had lots of rocks and the idea was push heat through the rocks and then let then store the heat. It really didnt work and radon was big issue as many Maine rocks can give off radon.

I have seen the concept of house with house "core", all the plumbing is in small area that is super insulated if its in tight basement the piping stays above freezing. Wells can be equipped with automatic drains that drain back into the well. Composting toilets can be mounted indoors and require no heat.

 

[WoodGirl]

I am guessing you would have difficulty affording insurance with wood only heat.

Actually, it is having a metal box inside one's home with a fire burning that the insurance companies frown upon.

 

[all night moe]

I have posted this numerous times in other threads....but here it is again.

Heating 4500sq ft with wood. Back up heat is more wood. There is an oil furnace. Collecting dust since 2007, along with the 1000 gal tank.
Using a woodstove in the living room of this 1830s/1906/1920s farmhouse. Wood furnace in basement tied into duct work.

Went through 11 cord plus with no stove. Just the furnace. Mix of hard and softwoods. This year running just the stove 95% of the time, i'm on my 6th cord.

Back up plan if I get hurt? Sit back and watch the slacker inhabitants of the house scramble for heat. I deserve it after 2 winters so far.

 

[begreen]

I have seen the concept of house with house "core", all the plumbing is in small area that is super insulated if its in tight basement the piping stays above freezing. Wells can be equipped with automatic drains that drain back into the well. Composting toilets can be mounted indoors and require no heat.

That is one thing that is right in our house, there is no outside wall plumbing. The other thing is that our pit basement and crawlspace are insulated. This keeps that area above 50º regardless of how cold it gets.

 

[bholler]

Same here no. Plumbing in exterior walls here either. Well I guess the washing machine is on an exterior wall but that part is below grade no real danger of freezing there and there is 2" or rigid foam behind it regardless

 

[wjohn]

1. What is the building spec?
~800 sq. ft, single story, crawlspace, R-11 walls, ~R-28 ceiling, recently added housewrap and replaced windows but still have some air leaks in the ceiling and an uninsulated/poorly sealed attic door to address

2. What are the stove(s) you are using?
VC Aspen C3

3. Do you have plumbing and what do you do to manage temp stability?
Yes, none on exterior. Plug-in electric baseboard heaters set to keep house above 50 degrees; only used when gone
Edit: Realize I am cheating here per your post intent. The heaters are more of a backup in case I don't make it home some night. They rarely come on unless I know I will be gone for more than a day or two.

4. What is a typical overnight burn experience in zero or subzero temps?
Load stove up before bed. Reload when waking up for day or earlier if up at 4am for whatever reason. Zero or below is more like 6 hours per burn cycle but I don't mind if the temp falls from 68 down to 60 by the morning if I sleep for 8 hours straight.

5. How much wood do you use in a day or a year?
Less than a cord (it was 70 here a couple of days ago and is going to be below zero the next couple of nights so I am not constantly burning... highs in the 40s and lows in the 20s are more average)

6. What is the daily temperature variance you experience in the building during zero/subzero temps?
60-70 degrees so about 10 degrees difference

7. Do you measure the moisture content of your wood?
Yes!

 

[wjohn]

I will also point out that the smaller the structure, the harder it is to let up on keeping a fire going. I grew up in a ~1200 sq. ft. house that had no backup heat source. I'm sure we came home once or twice to temps under 40 degrees inside after a couple day visit with family or something, but that house lost temp more slowly than my smaller house does. If I left my house for a day in zero degree weather without the electric baseboards on it would probably be not far away from freezing, especially with the crazy wind here.

When you get down to really small buildings, with no crawlspace/uninsulated floors etc. like I think I recall you have at least for the workshop, it's very hard. You can't really let off the gas (wood?), I guess, is what I'm trying to say because you will lose temp almost immediately. They don't have enough mass to retain heat for very long, like a larger house does. The insulation and air sealing become extremely critical for something that size if you are ever leaving it alone with no active fire in the stove.

You can oversize the stove so you can heat it up from dead cold relatively quickly, but then you have to be careful to not cook yourself out when you stick around for an extended period of time.

 

[richmhv]

1. Building spec- 1200 sq ft 1970's modular ranch . A foot of insulation in the ceiling, only the old 3.5" in the walls
2. Stove is a 2014 Jotul Oslo
3. House has plumbing. No problems with it freezing. Outside hose connections turned off an drained for the winter. I did run an electric heater in the basement on real cold days to make sure.
4. I have a roommate that is up till 2-3 am and I get up at 6 so no long overnight burns. Temps do not go below zero here too often anymore. but on real cold mornings, the house might be at 66 or so.
5. I use 6-7 cords a year, a little more with no backup as I sometimes need heat in the "warmer" months like May and September. 6 cords does the core November thru March
6. Central area of the house is usually 74-75 on average days and 70-72 on real cold days
7. No moisture meter, but I buy wood several months ahead split fine
I have an oil hot water system for backup and the burner gun failed. The plumbing/heating firms here wanted to sell me a whole new boiler rather than replace the gun, so I made it through 2 winters without it. The main pain is having to build fires on cool days in the warmer months. I finally did find someone to replace the burner gun so I can use oil for milder days. Wood is still my main winter heat. There is nothing quite like it.

 

[tabner]

It isn't a matter of cost at all here. Just finding the right company that will write a policy

This is true in my area also, I had a little experience with this. My father built a large post and beam off grid home (2500 sqft, granite foundation cemented all by hand on site, in northern VT) and the sole heat source is a huge masonry stove he built also out of granite that spans from the basement up into the second floor (open all the way around so you can view the whole thing from the ground floor). I called my insurance company (large national one, advertisements feature Jake or Aaron Rodgers), and they said under no conditions would they insure a home which has wood listed as the primary (and certainly not sole) heat source.

Actually, it is having a metal box inside one's home with a fire burning that the insurance companies frown upon.

Little more involved than this. All companies are going to take that metal box of fire into consideration when writing the policy, but i believe there is a difference between having a wood stove in your home, vs admitting that the woodstove is your only source of heat. The first scenario may result in a higher rate. The latter, as far as i know, will preclude coverage.

 

[KatieH]

We’re exploring a similar scenario for a seasonal cabin in WI. I’ve called around to insurance companies and have yet to find coverage for woodstove only (we’re far enough away from the volunteer fire department); for woodstove as secondary, it’s an additional $200/year in premiums relative to gas.

We’ll have a composting toilet and no running water.

We’ll have propane hooked up already for a gas range. In contrast, we’d have a forest full of hardwoods ready as woodstove fuel.

We’re trying to weigh
(a) woodstove with backup propane wall heater
(b) gas stove as primary heat

Any thoughts?