What is the Ideal Moisture Percentage to burn wood

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katwillny

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Is there a set moisture content that wood should be burnt at? Do different wood types have different sweet spots that they should be burn at? There may be previous threads, but I figure I'd get the conversation started.

thanks
Franklin
 
I tend to go by sound and feel but 20% and under is generally acceptable to burn.

Happy New Year
Pete
 
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You burn whatcha got. Sometimes you may have to clean the chimney often...

Ideally, you bang two pieces of wood together and they ring out loud and clear.

Matt
 
Loco Gringo said:
I re-cut about 1/2 cord 2 yr split oak yesterday and checked each piece before removing from the frame, and 9 outa 10 were 14-17 percent. Im thinking thats pretty good yeah?

Yes, real good Loco! And for the OP, with a standard moisture meter, I believe that 25% and less is considered fine for the stove. Measure from the face of a fresh split piece of wood. Cheers!
 
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KatWill said:
Is there a set moisture content that wood should be burnt at?

The driest you have the time and space to get it. You are not going to over dry wood if air drying in upstate NY.
 
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Size of fuel is also important. These are commonly used charts for determining wildfire potentials:

Fuels are classified into four categories by which they respond to changes in moisture. This response time is referred to as time lag. The four categories are:
•1-hour fuels: up to 1/4 inch in diameter.
•10-hour fuels: 1/4 inch to 1 inch in diameter.
•100-hour fuels: 1 inch to 3 inches in diameter.
•1000-hour fuels: 3 inches to 8 inches in diameter

Granted these are based on round fuels but it is possible that the % moisture you measure may be different (especially on smaller splits) by the time you burn it even if it's only a few days. I burn a lot of 2x4 mill ends that are kiln dried and burn really well and usually measure 12-15% moisture. Even if covered a few days of rain and high humidity will make them harder to start and the moisture can go above 20%. So the moral is you can dry a smaller split quicker but it also reacts quicker to environmental changes. If we start having a few days of rain and high humidity I usually bring in a few days worth of wood and put it in the basement.
 
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rwhite said:
Size of fuel is also important. These are commonly used charts for determining wildfire potentials:

Fuels are classified into four categories by which they respond to changes in moisture. This response time is referred to as time lag. The four categories are:
•1-hour fuels: up to 1/4 inch in diameter.
•10-hour fuels: 1/4 inch to 1 inch in diameter.
•100-hour fuels: 1 inch to 3 inches in diameter.
•1000-hour fuels: 3 inches to 8 inches in diameter

Granted these are based on round fuels but it is possible that the % moisture you measure may be different (especially on smaller splits) by the time you burn it even if it's only a few days. I burn a lot of 2x4 mill ends that are kiln dried and burn really well and usually measure 12-15% moisture. Even if covered a few days of rain and high humidity will make them harder to start and the moisture can go above 20%. So the moral is you can dry a smaller split quicker but it also reacts quicker to environmental changes. If we start having a few days of rain and high humidity I usually bring in a few days worth of wood and put it in the basement.

Thanks Rwhite, this helps
 
Feels like dry like a popcorn fart, sounds like a bowling pin when you bang it together... All this is a good thing. I don't have a moisture meter but I will never burn wood less than a year old again either. I know well that I may not be burning the best wood but it is better by a factor of 10 compared to what I had done in the past! Thanks to Brother Bart and Backwoods Savage for telling and showing what seasoned wood is.
 
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I have never been concerned with moisture content. I simply give the wood time to dry and it burns great.


EDIT: Perhaps I should have worded that a bit different. I am concerned about moisture content but have never been concerned at what % moisture the wood is. We just simply dry the wood and burn it. It works amazingly well and is very simple to do with no special tools required.
 
Thanks Dennis. I think i was just trying to justify the expense and if it would be worth the money to get a MM. I do got a birthday coming and all so I have to give the missus ideas. But I understand the need to dry wood properly to eliminate creosote. Thanks all for your replies.
Franklin
 
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Loco Gringo said:
I re-cut about 1/2 cord 2 yr split oak yesterday and checked each piece before removing from the frame, and 9 outa 10 were 14-17 percent. Im thinking thats pretty good yeah?

That's typical of wood here, on bringing it in from pile. Mind that this year's drying season morphed into super-soggy season with all the rain.

Storing it near the woodstove for a while takes the MC down quite a bit more. The really good stuff gets more such time than the crap.

NO SUCH THING as "too dry." If you think so, I'll relieve you of it. Claims of such are purest BS, IMHO and that of my lil Morso.
 
KatWill said:
Thanks Dennis. I think i was just trying to justify the expense and if it would be worth the money to get a MM. I do got a birthday coming and all so I have to give the missus ideas. But I understand the need to dry wood properly to eliminate creosote. Thanks all for your replies.
Franklin
If your trying to justify the expense put a new maul or chainsaw on the list of gifts for your B-day.
 
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RNLA said:
KatWill said:
Thanks Dennis. I think i was just trying to justify the expense and if it would be worth the money to get a MM. I do got a birthday coming and all so I have to give the missus ideas. But I understand the need to dry wood properly to eliminate creosote. Thanks all for your replies.
Franklin
If your trying to justify the expense put a new maul or chainsaw on the list of gifts for your B-day.
Already got me two Mauls, a 6lb and an 8lb. Also have my trusty Poulan 18 and the little Homelite 14 for smaller logs. The Homelite is always on the trunk of my car in case something catches my eye on the way to and from work.
 
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katwill, you need to do a search for some of the charts that battenkiller did. theres one graph in particular that will help you understand the relationships between mositure, heat output and efficiency. once I saw these, bingo, lights went off for me. I think that thread may be titled "can my wood be too dry". not sure.
 
oldspark said:
I just took out a loan on my MM, I think the payment was $1 a month for a year.
Glad to see you took on that financial commitment there Oldspark, I plan to follow suit as soon as I finish paying off my matches. ;-)

Probably the biggest and most common failure new, and old, wood burners make again and again is burning wood that is not properly dried. The simplest, most accurate way of "measuring" the moisture content of wood is with a moisture meter. Next to matches a moisture meter is one of the cheapest wood burning tools a person can buy. nuff said
 
Anybody?
 
anybody what?
 
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The simplest, most accurate way of "measuring" the moisture content of wood is with a moisture meter. Next to matches a moisture meter is one of the cheapest wood burning tools a person can buy. nuff said
I agree, and the $12 Harbor Freight meter works as good as the $30 General Tools meter. Yes there are more accurate more expensive meters but not necessary for fire wood.
If U are 3 years ahead I guess U wouldn't need one, If U have 30 years experience burning wood maybe U don't need one but , If just starting out, I think it's a must have tool and , I for one, would never be without one .
We have the technology ,and it is affordable , why not use it ?
Even if U have to burn what U got, at least U know what U got

EDIT 25% MC will burn 20% is better, Under 20% is best.
Yes U can burn wood above 25% but U will have several problems
 
20% and below, I burned some oak last year that was 22-23% and it was ok, higher than that and I really notice a difference.
 
20% and below, I burned some oak last year that was 22-23% and it was ok, higher than that and I really notice a difference.
I like the way it catches when it's down about 18% or less, but the EPA test wood is at 20% wet-basis, which would read 25% on a meter. When I burn 25% wood, it is hissing like a perturbed cat when catching. :oops:
 
My personal numbers, HF MM w/ fresh battery

popcorn fart/ kiln dry = 8% ( this will float depending on ambient conditions) kindling
Optimum burn 12-15 % ( this can take 3 or more years for Oak / Hickory or similar longer if using really big splits over 6-8"my area)
15-20% will burn ok in my units but heat output reduced ( at this range sounds like a baseball bat but I can feel the difference when burning)
20-25% still wet behind the ears( not spiting but got to run with the primary almost wide open for a good portion of the time) only use if desperate
25% and above might as well pay the utility company or buy compressed wood logs, Generally defeats purpose of burning wood in the first place. Wallet deflaters.
 
Blades numbers are off of what mine would be, any thing below 20% seems to be fine in my stove, not sure if I can get much below 15% any way.
 
Is there a set moisture content that wood should be burnt at? Do different wood types have different sweet spots that they should be burn at? There may be previous threads, but I figure I'd get the conversation started.

thanks
Franklin
Since we don't have any Oak, our firewood is stacked for a minimum of 2 years then it's ready for burning, I never use the M/M anymore. When we did it was 20% or under.
 
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