Moisture content question

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Mr.real

New Member
Apr 10, 2017
11
Ontario canada
so I have a few different piles of wood that I wanted to check the moisture content of to see what the difference is. I have wood that has been split and stacked for 2 winters. When I split a piece and check moisture it is 21%. My pile that has been split and stacked all summer with a tarp elevated with skids on top measures 23%. Now the blocks that were cut up and left in the woods in the winter that I split today measured at 25% moisture content. I am wondering how my differently treated wood is so close in moisture content.
Is this wood going to burn in my bk king or should I be lookin for more wood?
It's all maple. Thanks in advance
 
As I understand it, some wood throws off most of its moisture quickly after splitting pretty much regardless of the conditions. It's the last few percentage points that take a while and benefit from being elevated and covered. Maple is known to dry fast.

I can't speak to your stove, but it's a popular one so I'm sure you'll get some good specific advice as to its suitability.
 
Mr.real, what kind of species of wood are we talking about.. soft wood or hard woods?
If the hard wood is at 21% and the soft wood is at 23% and you have 2 cords each I would start off with the 23% stuff first and then in the depths of winter switch to the hardwood.
Also it's only mid September the next 6 or so weeks are going to offer to good drying time due to the colder less dence air that is going to filter in, hopefully your piles are exposed to wind, you may drop a couple moisture points.
I'd go on tarp duty, take them off during clear weather and cover during rainy weather
 
The wood is 90% sugar maple. A bit of ironwood, beech and elm. I have skids piled on my wood pile with tarps on that. A good 6 to 8 inches air space on the top of the pile. Should I still put the tarp on and off with good weather? I want the best I can get
 
The wood is 90% sugar maple. A bit of ironwood, beech and elm. I have skids piled on my wood pile with tarps on that. A good 6 to 8 inches air space on the top of the pile. Should I still put the tarp on and off with good weather? I want the best I can get

Yes, if it's in the sun, take the tarp off. I don't do that here because I would be covering it two or three times on your typical day. But it sounds like you would need to remove a bunch of pallets too? Probably easier to just stack it into single wide rows (traditionally) and top cover it. That way it can get sun without having to run outside every time it rains.
 
The difference in MC could be due to any number of factors such as different species, particular tree of a certain species, contact with the ground, exposure to sun and wind in the particular location, how the wood was stacked, etc. I think the point is that you have a 21% pile in mid September, and that would be good enough for me. Would it better to have 18% wood? Sure, but you are fine IMO.

Just start burning the 21% and move on to the 23% pile when the first pile is done. By that time, the 23% will be even more dry and like kennyp said the 21% pile will probably notch down a bit before you start burning as well. Wood continues to dry over the winter as long as it is top covered and gets some wind exposure. I'm not sure I would bother with tarp duty but it can't hurt.

In any event, I wouldn't go looking for more wood as your chances of finding wood that is even more seasoned at a reasonable price are probably low.
 
Wood continues to dry over the winter as long as it is top covered and gets some wind exposure.

That is climate dependent. A number of areas have cool/humid enough winters that wood at 23% will stop drying for some or all of the winter. Especially if it's exposed to ground moisture.


I'm not sure I would bother with tarp duty but it can't hurt.

I recommended removing the tarp during clear weather (or stacking the wood traditionally) because it sounded like some of the wood was simply piled on the ground with pallets thrown on top to create an airspace under the tarps. If that's the case, the ground moisture is increasing the humidity in the pile and removing the tarps will help considerably. There is a difference, in my mind at least, between a "stack of wood" and a "pile of wood". Apologies if that's not the intended message.
 
So I have a question regarding the use of moisture meters. Most say to have the wood up to room temperature before the reading since it will give a false low reading.

Is that true? And if so about how much lower is it? I know that climate and humidity affect it too but if I have wood that I split and measure at about 12% outside on a sunny 75 degree day how true is the reading?


Lopi Rockport
 
The wood is 90% sugar maple. A bit of ironwood, beech and elm. I have skids piled on my wood pile with tarps on that. A good 6 to 8 inches air space on the top of the pile. Should I still put the tarp on and off with good weather? I want the best I can get
Just a transient thought, I have been told that ironwood is so dense it is unsafe to burn as firewood because it burns so hot. I'm far from an expert, maybe someone else will be more knowledgeable but just thought I would mention.
 
That is climate dependent. A number of areas have cool/humid enough winters that wood at 23% will stop drying for some or all of the winter. Especially if it's exposed to ground moisture.
I totally agree, and should have noted that. But, the OP is in Ontario so I'm going to guess that dry winter wind will keep seasoning his stacks.
 
Hey thanks for all the quick replies. So my pile which is 6rows wide 15 feet long piled on skids, 2 rows per skid with air space between. Usually I wouldn't tarp my pile but all the rain this year made me cover it. And by covered I mean just the top of the skids not down the sides at all. I removed the tarp today as we are. Looking at sun and 27c for a week. This has reassured me to not go looking to buy wood. At 350 a cord for who knows what wood it wasn't very appealing. Thanks for all the input
 
Hey thanks for all the quick replies. So my pile which is 6rows wide 15 feet long piled on skids, 2 rows per skid with air space between. Usually I wouldn't tarp my pile but all the rain this year made me cover it

Sounds like you have wood stacks, not a woodpile:

[Hearth.com] Moisture content question

I think you'll be fine!
 
I know that climate and humidity affect it too but if I have wood that I split and measure at about 12% outside on a sunny 75 degree day how true is the reading?

75 should qualify as room temperature.
 
Just a transient thought, I have been told that ironwood is so dense it is unsafe to burn as firewood because it burns so hot. I'm far from an expert, maybe someone else will be more knowledgeable but just thought I would mention.

Any wood is fine to use as firewood, as long as it not poisonous, such as would be found with something like poison sumac. Smoke from poisonous plants is not good. The only consideration of the "burns to hot" thing may have to do with pine, as it does ignite quick and burn rapidly. This can, however, be dealt with by not using an abundance of small splits at same time.
 
The 21-23% stuff is close enough to 20%. I would rest easy, the King will barely be able to tell the difference.
 
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I have a very long single stack for "just split" before it goes to two locations near the house. I've had excellent luck top covering with clear plastic 2" wide and however many feet long. Since it's not direct sunlight, I'll get 2-3 years out of the plastic since there's no UV to speak of.

There's a clear difference in the top 2-3 spits under the plastic than further down the stack. I use a staple gun to tack the plastic down to the sides of the stack. This shot is from 2015 and I'm going to use the same plastic again this winter. Seems to stay on in most all weather.
[Hearth.com] Moisture content question
 
I have a very long single stack for "just split" before it goes to two locations near the house. I've had excellent luck top covering with clear plastic 2" wide and however many feet long. Since it's not direct sunlight, I'll get 2-3 years out of the plastic since there's no UV to speak of.

There's a clear difference in the top 2-3 spits under the plastic than further down the stack. I use a staple gun to tack the plastic down to the sides of the stack. This shot is from 2015 and I'm going to use the same plastic again this winter. Seems to stay on in most all weather.
View attachment 200342
What is the difference between the top 2-3 splits and the lower layers? Are the top layers drier than those below? Was thinking about a similar setup myself.
 
What is the difference between the top 2-3 splits and the lower layers? Are the top layers drier than those below? Was thinking about a similar setup myself.
I would think so also.. with that huge long pile I bet the 1st 2 or 3 split rows equal close to a half cord of wood
 
as it warms vapor rises so the top area ( with plastic down over the edge) will hold that vapor creating an environment not great for drying. if there is enough wind a lot of the rising vapor will be blown out the sides as it rises. so you need sufficient clearance between stacks to allow this to happen. its always a challenge to set things up to dry properly with in the constraints of urban areas and the local gov. regs. Even more so when they tell you what amount you can have on hand and other various ludicrous rules created by those with no knowledge in this area. ( me I got the x out of dodge- had enough of the regulation pasture droppings)
 
What is the difference between the top 2-3 splits and the lower layers? Are the top layers drier than those below? Was thinking about a similar setup myself.

The top few spits under the plastic are always drier than those further down. You pick them up and get that "weightless" sensation. It's got to be the result of a little bit of sun and NO rain.
 
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I would think so also.. with that huge long pile I bet the 1st 2 or 3 split rows equal close to a half cord of wood

I added another 8' last year, primarily, just because. ;) And I certainly have scavenged the top row when winter hangs on longer than expected!
 
What is the difference between the top 2-3 splits and the lower layers? Are the top layers drier than those below? Was thinking about a similar setup myself.

With the system I've been using the top layers are the driest. These fiberglass roofing panels let the infra-red heat through and also concentrate light breezes through the stack (especially the top). The bottom layers by the ground stay drier than with tarps because tarps deposit all the water from the top to the ground around your pile, increasing soil humidity. These corrugated panels channel all the water away, to the end of your pile.

[Hearth.com] Moisture content question


This photo was taken near noon but it's red (like a sunset) due to all the forest fire smoke in the atmosphere. During actual sunrise/sunsets I saw colors I've never seen before. Now that it's been raining for the last 3 days, I can see a nice dry spot all the way around the base of my stacks that I never had when I just used tarps.
 
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as it warms vapor rises so the top area ( with plastic down over the edge) will hold that vapor creating an environment not great for drying. if there is enough wind a lot of the rising vapor will be blown out the sides as it rises. so you need sufficient clearance between stacks to allow this to happen. its always a challenge to set things up to dry properly with in the constraints of urban areas and the local gov. regs. Even more so when they tell you what amount you can have on hand and other various ludicrous rules created by those with no knowledge in this area. ( me I got the x out of dodge- had enough of the regulation pasture droppings)
I agree about the vapor rising up, but I loose you there, I would think that it rises, condenses on the plastic and rolls off the plastic, sparing the wood splits for gaining extra moisture.
 
This photo was taken near noon but it's red (like a sunset) due to all the forest fire smoke
Horrible that you guys have fire problems, but beautiful picture, love the lighter / brighter colors.