new videos
hot off the press!  
    more about rocket
mass heaters here.

more videos from
the PDC here.
  • Post Reply Bookmark Topic Watch Topic
  • New Topic

Recommend me a small style heater for a small, leaky space?  RSS feed

 
Mike Cantrell
Posts: 555
Location: Mid-Michigan
28
bee books duck food preservation forest garden hunting solar trees
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi all,

I'm cleaning up a small outbuilding to be a home office. I work from home at least a couple of days per week, so I'll be in the building all day when I'm in there.
In mid-Michigan, daytime temps are, say 0-20F in the winter, depending on the week.

It's a 12' hexagon, which makes about 156 SF of floor, and 1248 CF of air. It has a ceiling fan to stir the hot air down from the ceiling, and a concrete chimney (ceramic flue) already going out the wall about eye-level, then up above roof height (say, 10' tall).

I'd like to build a small thing to burn wood in and stay warm. I can rustle up metal parts probably as needed, and I have plenty of clay and fieldstones.

Actually, here are photos.







What kind of heating appliance would be easy and effective for a space of this size and type?
On the one hand, it's not much air volume. On the other, I won't get around to insulation and "tightening" until next year, probably. So it's quite, quite drafty.

Recommendations?
Thanks!
Mike
 
Lyvia Dequincey
Posts: 45
2
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I would say first thing is windows on the south and insulate the north, but then I'm in Virginia. But you want an effective heater for a leaky without insulation? You might need to start at least the north side and the roof. Then plant a windbreak bush or two on the north side.

The smallest woodstoves I've seen are the little marine ones. So cute!
 
allen lumley
pollinator
Posts: 4154
Location: Northern New York Zone4-5 the OUTER 'RONDACs percip 36''
58
books fungi hugelkultur solar wofati woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Mike Cantrell : Not much Direct help here I'm Afraid, Your space is so small that at best most stoves would be to big, A small 'laundry stove'' on very short legs and smaller than
a foot locker would be equal the most cold days.

You might have to start the fire like starting the car before you go to work, go back inside for that 2nd cupa'- keeping a eye on your chimney and windows- exactly the same way
you should check on your Car !

What is the round cap on the top of your office ! It looks like it might be there for ventilation, blocking it in such a way that it could be removed easily the 1st time you over-heat
your office will be a natural that will pay you back for the time you put in it !

Ideally, your fire will heat up your space and be burned down to a bed of coals and you can close your damper most of the way, Always remembering to open the damper before
Opening your wood stove door !!! and throwing in several small pieces at a time to 'keep off the chill''. Small wood warms more efficiently and faster than Everything else !

You are probably going to have to move the shelving to another location! In the third picture you have a piece of what looks to be a re-cycled piece of metal roofing, in the picture
it looks like it is fastened down directly to the wall ! THIS IS WRONG !You most have and air space of 2''-3'' between the metal and the wooden wall though you can get away
with short narrow pieces of wood to give you that spacing! A little wider than what I see would be Much safer ! Notice the Way the paint is chipped and cracked at a hot spot at the
place where the Ceramic Thimble enters the living space from he outside chimney, A larger hole around the Ceramic Thimble is better than what you have here ! A mirror surface
or at least a light color is best !

The picture also tells me that at some point there was probably another larger piece of metal flashing or roofing, below the 1st one ! There has been a past problem will water vapor
condensing out of the air against the cold outside wall lifting the paint and starting to rot the wood at floor level ! Again, the stand-off of the lite-colored flashing from the wall allowing
an air exchange is the solution to this problem ! This is counter intuitive to some people ! As long as the air gap is there and the material is light colored,it can even be a sheet of
mylar, heavy weight aluminum foil, or roll flashing ! The gaps should be complete (though they can overlap ) at the top and bottom and generally open at the sides,

Consider going to a farm supply store and asking them for the cheapest ceramic or insulative plastic shapes that can be used for stand offs !

As the cheapest way to Protect the floor from the same radiant heat energy we protected your walls from, I would recommend glueing a heavy-weight Aluminum foil directly to the
floor, sweeping and moping and drying the floor 1st ! Then placing cement pavers directly above it. the final dimensions should be at least 8'' wider away from an outline of the stove
traced onto the pavers ! I would not use full-sized 'cinder blocks' to raise the wood stove 'higher off of the floor' because you will always have Cold Feet !

Your outside door is in terrible shape mostly because it is a hollow core interior door, you will have to remove the door from its hinges and get it up on saw horses to see if you can
salvage it ! I expect that you will find that the bottom piece of wood is 'hanging by a thread', we want to work the original piece out at the bottom so that we can get its dimensions
then we can slide in replacement pieces of wood of the same thickness , we are not trying to fill the gap between the inner and outer skins of the door, just saving the door! The final
step here is attaching a rectangle of Roll roof flashing to the inside and outside of the door ! It will not 'look odd' it will look just like a kick panel that only comes on more expensive
exterior doors !

I always recommend the storage of at least one heating seasons wood fuel ahead, protected, out of the weather, You have a beautiful Car Port To store your fuel out of the weather,
I am strongly recommending that you cover the back wall of the Car Port with a tarp, extending it from the car port to the closest side of 'your office', the tarp will act as a wind break
and save you a 1/2 cord or more in fuel ! Another piece of tarp going back to the next near corner of the Car Port would be even better !

The worst case - you go to work in a snowmobile suit and never leave the yard ! I hope this is timely enough to be of some help ! For the Good of the Craft !

As always, your comments, and questions are solicited and Welcome ! Think like Fire! flow like a Gas, don't be the Marshmallow ! PYRO - Logially Big AL !
 
Peter van den Berg
gardener
Posts: 519
Location: +52° 1' 47.40", +4° 22' 57.80"
61
forest garden trees wofati woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The floor of the office-to-be is wood, plus you are not living in there. A mass heater isn't suitable when you are away from it more often than not. When it is a rocket of some sort you want you could build one of my experimental models. See this webpage of Donkey's forum, the first page is showing a drawing.

You could build the j-tube yourself or use a 4" commercial dragon core. Should be powerful enough to heat the place, is only hot when you keep feeding it. Of course, there are other stoves which could do the job, but they need a lot more fuel and won't burn as cleanly as an optimized rocket heater. The other side of the coin: not possible to use cord wood, the pieces of wood shouldn't be wider than 1" square approxmately. splitting wood that thin for the entire working day would consume about half an hour or you could use branches.
 
Michael Cox
Posts: 1659
Location: Kent, UK - Zone 8
54
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Alternatively, do you need to heat the whole space? What about using an electric mattress topper and giving yourself a heated seat.

Also, why not insulate it? At the very least you could plug a lot of drafts, and perhaps staple some fiber insulation to the internal walls.
 
Mike Cantrell
Posts: 555
Location: Mid-Michigan
28
bee books duck food preservation forest garden hunting solar trees
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Lyvia Dequincey wrote:I would say first thing is windows on the south and insulate the north, but then I'm in Virginia.


Thanks, Lyvia. I'm going to replace that busted door with a proper exterior door with glass lites, so that will be a start. (The door faces directly south.)

Allen Lumley wrote: What is the round cap on the top of your office ! It looks like it might be there for ventilation, blocking it in such a way that it could be removed easily the 1st time you over-heat
your office will be a natural that will pay you back for the time you put in it !


Thanks, Al! you know, I'm not sure what the original purpose of that cap was. Now, there's a ceiling fan hung below it, so it doesn't open.


Allen Lumley wrote: You are probably going to have to move the shelving to another location! In the third picture you have a piece of what looks to be a re-cycled piece of metal roofing, in the picture
it looks like it is fastened down directly to the wall ! THIS IS WRONG !You most have and air space of 2''-3'' between the metal and the wooden wall though you can get away
with short narrow pieces of wood to give you that spacing! A little wider than what I see would be Much safer ! Notice the Way the paint is chipped and cracked at a hot spot at the
place where the Ceramic Thimble enters the living space from he outside chimney, A larger hole around the Ceramic Thimble is better than what you have here ! A mirror surface
or at least a light color is best !

The picture also tells me that at some point there was probably another larger piece of metal flashing or roofing, below the 1st one ! There has been a past problem will water vapor
condensing out of the air against the cold outside wall lifting the paint and starting to rot the wood at floor level ! Again, the stand-off of the lite-colored flashing from the wall allowing
an air exchange is the solution to this problem ! This is counter intuitive to some people ! As long as the air gap is there and the material is light colored,it can even be a sheet of
mylar, heavy weight aluminum foil, or roll flashing ! The gaps should be complete (though they can overlap ) at the top and bottom and generally open at the sides,

Consider going to a farm supply store and asking them for the cheapest ceramic or insulative plastic shapes that can be used for stand offs !


Thanks! I knew this was no good, but I didn't have a clear idea of how I should remedy it. What you've described sounds straightforward enough, I think I'll go that route.

Allen Lumley wrote: Your outside door is in terrible shape mostly because it is a hollow core interior door...


It's in even worse shape than the picture shows. I'm going to replace it with something sensible.

Allen Lumley wrote: I always recommend the storage of at least one heating seasons wood fuel ahead, protected, out of the weather, You have a beautiful Car Port To store your fuel out of the weather,
I am strongly recommending that you cover the back wall of the Car Port with a tarp, extending it from the car port to the closest side of 'your office', the tarp will act as a wind break
and save you a 1/2 cord or more in fuel ! Another piece of tarp going back to the next near corner of the Car Port would be even better !


Absolutely. I'll be heating the house with wood, too, so the reserve will be plenty big to serve the office too.

Allen Lumley wrote: The worst case - you go to work in a snowmobile suit and never leave the yard !


That's what I'm trying to avoid. Four or five layers I don't mind, but sitting all day in the serious winter gear, I'm not crazy about.

Peter Berg wrote: The floor of the office-to-be is wood, plus you are not living in there. A mass heater isn't suitable when you are away from it more often than not. When it is a rocket of some sort you want you could build one of my experimental models. See this webpage of Donkey's forum, the first page is showing a drawing.

You could build the j-tube yourself or use a 4" commercial dragon core. Should be powerful enough to heat the place, is only hot when you keep feeding it. Of course, there are other stoves which could do the job, but they need a lot more fuel and won't burn as cleanly as an optimized rocket heater. The other side of the coin: not possible to use cord wood, the pieces of wood shouldn't be wider than 1" square approxmately. Splitting wood that thin for the entire working day would consume about half an hour or you could use branches.


Thanks, Peter! I'll read up on these links.

Michael Cox wrote: Alternatively, do you need to heat the whole space? What about using an electric mattress topper and giving yourself a heated seat.

Also, why not insulate it? At the very least you could plug a lot of drafts, and perhaps staple some fiber insulation to the internal walls.


Thanks, Michael. I think I do need at least some level of space heating. Windy and 0F is too cold for me even with heating appliances touching me.
And I'm going to insulate it! I'm just trying to be realistic about what I can get done this season. We bought this place in December, and I worked on making it habitable until June (you can only chip away at it a little at a time with a full-time job, two kids, and wife nine months pregnant ), then we moved in. Now I've still got things to work on, but I've got to pick my battles. Getting the office insulated might happen... but then again it might not. So I figure I should plan for the worst, you know?


 
Satamax Antone
gardener
Posts: 2280
Location: Southern alps, on the French side of the french /italian border 5000ft high Southern alpine climate.
55
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Duh, nobody seemed to have said pocket rocket
 
allen lumley
pollinator
Posts: 4154
Location: Northern New York Zone4-5 the OUTER 'RONDACs percip 36''
58
books fungi hugelkultur solar wofati woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Mike Cantrell : This will most probably not work for you if you have to entertain paying Clients, but - go to our sister site ' richsoil.com ' and click on Electrical Heaters,
don't forget to check out local want ads, 'penny savers,' 'crags list,' and my favorite Habitat for Humanities RE-Stores! Lots of free or cheap supplies for tightening your office.
Like a exterior door! If you don't score a small laundry stove a 5 gal metal pail can be turned into a pocket rocket for little more than the stove pipe you would have to have
any way- while you are scrounging materials, don't forget the tarp/plastic materials for your wind breaks ! Hope this helps ! For the Good of the Craft !

As always, your comments and questions are solicited and are Welcome ! Think like fire, flow like a gas, Don't be the Marshmallow ! PYRO - Magically Big AL !
 
Hey, sticks and stones baby. And maybe a wee mention of my stuff:
2017 Rocket Mass Heater Workshop Jamboree - 15 workshops in one event
https://permies.com/wiki/63312/permaculture-projects/Rocket-Mass-Heater-Workshop-Jamboree
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!