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heating with green wood

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
So here I am in a new place and I don't have near enough wood in.

And what I do have is wet. Or green.

And it has been raining to beat the band here for weeks. So even if I find the driest snag around, it's still gonna be wet.

So I'm shoring up on my strategies for burning green/wet wood.

I know that I need a super hot fire every day in order to burn out any potential creosote. I have that covered.

I've been working on trying to get a fire started in the morning with the smallest, driest wood and then tossing in the lousier stuff later in the day.

I've build a huge wood rack and keep it near the woodstove in the hopes that it will dry wood a bit for the next day.

I am tempted to come up with some metal to put on top of the stove that will allow me keep a stove load of wood directly above the wood stove. My thinking is that if it touches the woodstove, that would be too hot and could ignite. But with a couple of inches, that might be enough to not ignite. But my heebie jeebie factor is too high so far. I'm wondering if anybody has any advice about something along these lines: something where today's fire can dry out some wood for tomorrow morning.


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paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
You big bunch of weenies!  Pbpbpbpbpbtttt!!!

Okay, so it turns out I'm too much of a weenie myself to to put wood on top of the stove to dry it.  And I think that's for the best.

In all of my research I did discover one new tidbit that is excellent info:  think of wood as a big wad of straws - it dries faster sitting on its end than it does sitting on its side.  One person went so far as to say it would dry ten times faster!

Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
If all you have is green wood, you're going to have creosote buildup no matter what you do, because the fires just aren't going to get hot enough.

I don't know what your wood storage setup is like, but the best is a covered shelter (with overhang against blowing rain), open into the prevailing wind, with an opening on the opposite side so the air can move through the shelter, Stack your wood crisscross-wise, with space between all the pieces. But it still takes time.

You might want to post a request on your local FreeCycle board for dry wood that could be used for firewood, and be sure to specify UNTREATED.  Old dry fir 2x4s or 2x6s aren't ideal, but they're not going to put any more pollution into the air than burning green wood. 

TIP for dealing with FreeCyclers:  If you do get someone who has something you need, please don't pick it up in a brand-new pickup truck or Lexus! It drives me crazy to give something away on FreeCycle, hoping some poor person can make use of it, and then have some bozo in a $50,000 truck come for it.  Go in an old rattletrap and say 'thank you' several times, and they may toss in some other useful stuff.  People hate being taken for suckers.

Sue
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
So I have a "stovepipe thermometer" that sits on top of the stove (I suspect that a thermometer on a triple pipe would be pointless) and pegs out at 900 degrees.  I guess I should say that I've been pegging it out almost every day.  So I guess my next question would be:  what is "hot enough"?  I'm pretty sure I'm way past hot enough, but I have to admit that I'm not absolutely certain.

Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
I don't know a thing about stove thermometers.  The thermometer or the stove should have a manual that can provide information.  Otherwise, call a stove place and tell them what kind of stove you have and ask where to put the thermometer.  I heard someone somewhere mention something about drilling a hole in the chimney for a thermometer, but I'm not even sure they were talking about a home-type chimney.

Sue
                                      


Joined: Nov 10, 2008
Posts: 92
Burning wet wood is not a good idea.

You're sending more pollutants up the chimney, and getting little return in the way of BTU's from that wood.

In other words, you are wasting firewood to get the same amount of heat from dry wood.

Is your firewood split?
If not, the best solution, no matter what size rounds you have, is to split it small and then let it dry next to the fire.


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Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
Here's a design for a solar wood dryer:  http://www.builditsolar.com/Projects/WoodDrying/wood_kiln.htm

Sue
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
Burning wet wood has challenges and is far less optimal that burning dry wood. 

The pollutants are more as long at the fire is not super hot.  There is a temp where the fire is just as clean whether the wood is wet or not.  I'm not sure what that temp is, but the fire does have to be very hot. 

Yup, splitting it all quite small so that it dries faster in the rack and in the firebox. 

I've been standing the wood on end next to the firebox for the next fire.  That has worked really well.

And ... I had a can of canned air that was sitting around for years.  That is now gone, but before it was gone it worked REALLY well for getting the fire really roaring hot!    In it's place I have one of those things that blows up an air mattress.  It works almost as well.

Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
I read somewhere that the problem is that burning green wood is working against itself, like trying to burn water.

I have dried wet seasoned wood on metal racks on top of my wood stove, but never left them unattended.

The cheapest wood I have access to is mill ends.  There was a guy who collected the cutoffs and scraps from a place that built trusses.  But since the building industry bottomed out, I guess my source has dried up. 

Sue
                                      


Joined: Nov 10, 2008
Posts: 92
paul wheaton wrote:
I've been standing the wood on end next to the firebox for the next fire.   That has worked really well.



After 11 years of using wood as the primary heat source, in 2 different houses, I can tell you I've done my share of that. At some point you end up drying out some stack of wood, wether because the rain blew in at your wood pile, or the snow got under your cover, it happens.
Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
Well, I got a load of mill ends today, a few hours after I posted here about probably not getting any this winter!

Whoohooo!

And it's all wet.  Not green, it's kiln-dried, but it has been sitting in the dump truck for a few days in all this rain.  Ten cubic yards of wet wood to put away... yippee 

Oh, well, at least it's wood. I'll just toss it ramdomly into the wood shed and hope it dries out.  As the last poster said, I've dried wet wood before burning it, too.  Someone stole about a quarter of my last batch 

Sue
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
Hmmm .... here is another odd thought ...  I bet that wood that is in a big jumble dries faster than wood that is stacked.    Two reasons:  1) more air can get in there, and 2)  Wood on its side dries slower than any other position - 90% of the wood in the jumble is gonna be not on its side. 



Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
That's what I thought, just toss it in in a jumble and let it dry.  A few years ago, I cut a 2'x2' hole in the east wall of the woodshed (the west is already open) so air can flow through.

Sue
                                      


Joined: Nov 10, 2008
Posts: 92
paul wheaton wrote:
Hmmm .... here is another odd thought ...  I bet that wood that is in a big jumble dries faster than wood that is stacked.     Two reasons:  1) more air can get in there, and 2)  Wood on its side dries slower than any other position - 90% of the wood in the jumble is gonna be not on its side. 




Yes, it will probably dry faster that way. Unless it is cross stacked in a breezy location out of the weather, stacking takes longer for drying purposes because of a lack of airflow around the wood itself. Only problem is with a pile the inner wood won't get much air either, but as the wood is used will be exposed and dry.
Leah Sattler


Joined: Jun 26, 2008
Posts: 2603
could it be stacked strategically to speed drying? alternating layers like this ll = with space between them? maybe up on pallets or something. I wonder if that would speed it up enough to make a difference. when we had a wood stove we always had plenty of seasoned wood so I have never had to purposely dry any.


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paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
I think the optimal stacking would be to have it all vertical:  ||||||||||

It might be optimal to have an air layer between layers of wood.

But I just don't see an obvious, easy way to do something like that.  So - the jumble stack rules! 

                                      


Joined: Nov 10, 2008
Posts: 92
Leah Sattler wrote:
could it be stacked strategically to speed drying? alternating layers like this ll = with space between them? maybe up on pallets or something. I wonder if that would speed it up enough to make a difference. when we had a wood stove we always had plenty of seasoned wood so I have never had to purposely dry any.



That's cross stacking, and it does speed up the drying over just stacking it up one on top of the other, simply because of better airflow.
It uses up a lot of space, and time though.
Kelda Miller


Joined: Jun 30, 2007
Posts: 763
The jumble may work better for another reason:
If, as Paul says, we should picture each stick of wood like a bundle of straw, then if it's standing on it's end
|||||||||||
it's standing On something. A piece of plywood or the ground or something. And the most effective way for that moisture to drain out is to be able to drain Out, for it to Not be standing on something (well, unless it's a screen of chicken wire or something, but that's another idea...)

The jumble of wood leaves those ends unimpeded for the most part.


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Kelda Miller


Joined: Jun 30, 2007
Posts: 763
I've actually just started stacking some of my piles this way, though a bit more organized than a jumble. Which leads me to the next question: how much faster does wood dry out when dried on end? And are we talking just for wet wood, or for curing green wood?

I was thinking of my ideal way of stacking in the various wood-shed contraptions I've got around here. I can definitely fit more the conventional stacking way, which works fine if I have a year to cure it. BUT, if I want it to cure faster, it takes up more space, how many months is that rotation?

Do you think it would still be about a year? or half a year? how much faster is this method?
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
The answer is:  it depends.

One person mentioned "20 times faster" - and based on a lot of my reading recently, I think that can be accurate.  But you have to put the log on end, and not have other bigs above pouring thier goo onto your log.  So there are trade-offs. 

Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
There are so many things that can affect the drying/curing of wood that few places would be the same.  Things that would affect drying (just off the top of my head):

Covered?
Amount of rain (100% humidity?)
Humidity?
How tightly stacked?
Are the ends exposed to moving air so moisture can wick out?
Under shelter that allows prevailing wind to pass through?
Stacked on dry ground or damp ground?

My wood shed is made of wood board and is attached to the back of my garage.  It has a fairly large door facing west (prevailing wind) that is virtually never closed.  I cut a 2'x2' hole in the eastern wall for air to move through and add light.  The outside of the window is loosely covered with a sheet of clear heavy plastic (WalMart by the foot) stapled at the top to keep out blown rain/snow.  When the wind blows, the plastic lifts up to let it pass through, then drops down again.  The floor is dirt and is always dry, but I've gradually been adding pallets as I get them and putting the wood on that.  (This is where little visiting dogs are taken to relieve themselves in deeper snow -- mini dachsies disappear in a foot of snow.)  The roof is metal, the inside walls are painted white to help reflect available light.

It could still use some light for when I need to go out there at night (poor planning, yes), but it works for now.

Sue

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
I saw something where somebody set up a sort of pallet system where the pallets of wood could be moved around as needed.  I would think that if you made a box, on a pallet, filled it with a jumble of wood and then covered it, It would probably dry faster 5 to 10 times faster than any stacked wood that is also covered.  And then, as needed, you could move this box where it would be easy to get at. 

So fill the box up where the trees are when you cut them.  When the wood is dryer, bring the wood to the house so it can be used.

Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
How would the average person transport pallets of wood from once spot to another?  How would they move it off the conveyance?

Sue
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
Excellent question for which I don't have a good answer. 

Tractor stuff is the first answer.  And without that ... well, there are lots of spots of moving ...  things that look like hand trucks would help.  Winches and the like might be a help.  I think one would need to get mighty creative.

Kelda Miller


Joined: Jun 30, 2007
Posts: 763
I think the tool we're looking for for that is the 'pallet jack'.

Voila:http://en.wikipedia.org/wiki/Pallet_jack.
The manual one.

Downside is that everything's got to be flat to easily move the wheels around.

Upside is that a friend and I and her baby managed a big delivery once without any heavy lifting or noise or danger to baby using one of those pallet jacks.

I wouldn't get one just for firewood moving.... But it's a great 'passive' (no fuel) way of moving big stuff around. It may be handy for someone in the neighborhood to have one.
Matt Ferrall


Joined: Dec 26, 2008
Posts: 555
Location: Western WA,usda zone 6/7,80inches of rain,250feet elevation
    
    4
People should never place wood directly on or with the potential of touching the stove.My landmate burnned his house down that way.He put it on the stove and went for a walk.1 hour later 50%less house!Cross stacked wood seems like it would be fastest.Mabey I dont understand,but how would air get to the center of a loose pile?Split wood will release its moisture easiest from the end grain,second best is the split side.The round outside will be most resistant to release moisture.With over 30yrs of living with a woodstove as my primary source of heat,the easiest way(in my experience)to dry wood in a rural area is to use pallets,slender cedar poles,old construction wood etc...for a base.Old metal roofing is used for the top with old rotty forest wood for weight on top.Wood is dried in situ and a wheelbarrow is used to transport the dry wood home.This avoids moving wet wood and needing a covered space.My neighbors used plastic for a top for years but the metal never has to be replaced so several oldtimers have converted to variations of this style.


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paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
As for how does the air get into a loose stack ...

I suppose the best answer to this question comes from definitions I have read about when buying a cord of wood. 

The proper definition is 4 feet by 4 feet by 8 feet, STACKED!  Apparently, a cord and a half loose is worth a cord stacked.  Therefore, what is between all the loose stuff must be good ole air.

Matt Ferrall


Joined: Dec 26, 2008
Posts: 555
Location: Western WA,usda zone 6/7,80inches of rain,250feet elevation
    
    4
Somehow I doubt that just because the volume of air between the wood is greater,It would dry the stack out faster.A cord is sold as that but it is often stacked in rows with air flow between rows.This allows the end grain exposure to a constant air flow which will take away the moisture.I would be interested in hearing how a pile works though.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
I think the idea isn't so much that there is more air, but rather that most of the wood grain is not horizontal - the "straw" in the wood can drain better when it is anything but horizontal.
Matt Ferrall


Joined: Dec 26, 2008
Posts: 555
Location: Western WA,usda zone 6/7,80inches of rain,250feet elevation
    
    4
Perhaps we disagree on what part of the wood releases the most moisture.The research ive seen shows the end grain as the most porous,which would make a horzontal stack the most efficient because it exposes the most end grain cuts.
Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
I think the difference might be whether or not the wood is split or just lengths of branches.  If split, it will probably lose moisture through the cut areas, and branches will just lose moisture from the cut ends.

Sue
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
I saw a picture of a chunk of wood on its side ... looking as you would expect it to look.  I can't remember the type of wood.  And then they took that same chunk of wood and placed it on end.  So the second picture was of it on it's end.  In a puddle.  Apparently the water came from inside of of the wood. 

So, yes, the ends are more porous.  Much more porous.  In this case, on its side, the water just sat inside the block of wood.  On its end, the water literally poured out due to the mighty power of gravity.

I think it was the caption with the picture that said something about imagine a block of wood as bundle of soda straws. 

Granted, some wood will hold its water better than others. 



Brenda Groth
volunteer

Joined: Feb 01, 2009
Posts: 4433
Location: North Central Michigan
    
    8
where i live most of the factories and lumber yards toss out  their pallets for free, they are generally made of oak..and dry..you'll have to sift out the metal before throwing the ashes in the garden.

also, lumber yards toss warped and other trash out behind their stores, asking the manager they might allow you to haul it off, as it cost them to take it to the landfill..it might not be oak but it isn't green.


Brenda

Bloom where you are planted.
http://restfultrailsfoodforestgarden.blogspot.com/
Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
You don't even need to sift the ashes.  Just get one of those handled magnets and stir it around in the ashes to collect bits of metal.  Works fine, I've done it for years.

Sue
Brenda Groth
volunteer

Joined: Feb 01, 2009
Posts: 4433
Location: North Central Michigan
    
    8
So I'm wondering how your adventure went with the green wood last winter..and if you are getting your wood put up for this coming fall?

we have had to use greenwood and it isn't good..we have heated with wood for 38 years..and sometimes you just run out and have to make do..we have had to stack wood next to our stove to dry..but it never will dry enough in one year to prevent creosote..

not sure how much you have studied..but it is best to cut your wood in the winter when the sap is out of the wood..so it is already drier..and then dry it out in the sun ..or under a tarp or cover to keep it from getting rained on.

then store it in a fairly open stack..with a few inches between cords when you put it up..this also helps the drying..mold can cause some serious health issues storing up wet wood.

best time to get your wood is in the winter..look for dead trees or cut them and leave them lie for a while if you have to..but get them off their roots in the winter before the sap rises.

use the summer months to get it cut up ..and then fall you can stack inside and split..and then start on next year's wood..also have some extra incase you have a more severe winter and run out..as we had the worst winter in 60 years here in Michigan and with two houses being heat..we went through 40 cord and still ran out early..

                    


Joined: May 10, 2009
Posts: 24
i used green wood for heating for 2 winters in the mountains in w/wa.  What i would do is split a big load really small and like it all around the wood stove so it would dry fast.  I would use that wood to get the fire super hot then i would load my large wood stove full of green wood and this would make for a long hot fire.  The wood closest to the core of the fire would sizzle out quickly and dry and the wood on the outsides would dry as the rest of the inner wood burned and once the inner pile fell in the more dried wood would fall to the center.

That was the only way i could get lots of heat from the wood. If i burned smaller loads it would not get verry hot and would waste the wood in my view.  Loading the fire packed full was the way to go for me.

Now on the pollution side i have no idea..;


www.myspace.com/lostchief
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14841
Location: missoula, montana (zone 4)
    ∞
I like the part about less sap in winter wood.  Cool!

I guess most of my research has been with how to use much, much less wood, in general:  the rocket stove stuff.

As for my own experiences:  The key is to have a very hot fire.  I figure if I'm gonna start a fire, I need to peg out the thermostat at least once.  It usually takes two hours of burning to get to that point.

And while I have a fire going, I keep a bunch of wood stacked on end near the stove.



Joel Hollingsworth
volunteer

Joined: Jul 01, 2009
Posts: 2103
Location: Oakland, CA
Two ideas, each overly-complicated due to engineering education:

A.  Make charcoal using the retort method:

1.  your green wood goes in a steel container (e.g., paint can), and as it pyrolyzes, flammable gasses are expelled from holes in the bottom.

2.  collect charcoal, re-fill retort

3.  the next fire, you start using dry stick wood, and charcoal, which will burn at least until the retort heats up enough to start giving off flammable gasses.

This way, all the creosote burns.  You may even net some charcoal to the bargain.

B.  Add a solar chimney to your woodshed.  HVAC tubes would work great, blackened on the sunward side with spray paint or soot.  If you happen to have lots of this, the air intake can be such a tube on its side...now you have a solar kiln, not a shed.


"the qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men.  They are manifestations of the laws of nature, free to all men and reserved exclusively to none." SCOTUS, Funk Bros. Seed Co. v. Kale Inoculant Co.
Erica Wisner
volunteer

Joined: Feb 10, 2009
Posts: 720
Location: Okanogan Highlands, Washington
    
  85
Lost Chief wrote:
i used green wood for heating for 2 winters in the mountains in w/wa.  What i would do is split a big load really small and like it all around the wood stove so it would dry fast.  I would use that wood to get the fire super hot then i would load my large wood stove full of green wood and this would make for a long hot fire.  The wood closest to the core of the fire would sizzle out quickly and dry and the wood on the outsides would dry as the rest of the inner wood burned and once the inner pile fell in the more dried wood would fall to the center.

That was the only way i could get lots of heat from the wood. If i burned smaller loads it would not get verry hot and would waste the wood in my view.  Loading the fire packed full was the way to go for me.

Now on the pollution side i have no idea..;


Now that we're back to "I gotta burn what I got" season,
I though I'd share this website: 
http://www.chimneysweeponline.com/howetwd2.htm

In addition to some "insider info" about how things burn (the sweep sees it all) it had me laughing out loud at the variety of ways the Sweep finds to say,
"ON'T BURN WET WOOD!"
He includes all the reasons why.  Dangerous, inefficient, polluting, can lead to deadly chimney fires, permanent damage to your stove and house, etc.

Splitting and drying your wood quickly will definitely help - so will building a proper woodshed and filling it NOW for next year.  (They have a diagram of how to build a good woodshed, too, pretty straightforward, a lot like Mt. Goat's description.)

I learned to stack wood crossways to dry II=II= like folks were talking about. 
I suppose you could do all kinds of things to dry it faster, like cook it in your electric oven or dehydrator - but in terms of doing it in an easy, neat, accessible, and reliable way, it's all about cutting it a year or two ahead, and keeping it dry until you're ready to use it. 
Splitting it will make a big difference in terms of drying time.

In solidarity with all parties involved, NEVER leave firewood near your woodstove unattended.  In fact, burning a woodstove unattended in the first place is not the brightest idea, though I know with your 24-7 woodstoves its inevitable.  We have a rocket heater, and we use it for a few hours a night when we're home to watch it.
  If you need to dry firewood quickly, stay in the room with it, don't let it touch the hot parts of the stove, and check it frequently.  If you need to leave, put the wood in a safe place - even letting the fire go out might not stop the quick-heated wood from spontaneously kindling itself from the leftover heat in the stove.
  The only Rocket Mass Heater fire I've ever heard of came from this situation: someone left a pile of kindling on top to dry, and wandered off.

That's my two cents! 
Good luck to everyone who's stuck with wet wood, and congratulations to those who put in a good supply of dry wood for this year.

-Erica Wisner

http://www.ErnieAndErica.info
(we have a long-winded Fire Science essay there if anyone's interested).


Play with nature, make nifty stuff:
www.ErnieAndErica.info
                    


Joined: Oct 23, 2011
Posts: 0
The surface area to weight ratio is a big factor in how fast it dried. Splitting it into smaller (thinner) pieces can speed things up, but it's work.  Running it through a chipper-shredder would boost the surface area incredibly and allow it to dry faster, but then you would have to burn it in a special stove.
 
 
subject: heating with green wood
 
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