Moisture meter

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tumm21

Member
Jul 16, 2011
212
North Jersey
I bought a General moisture meter at Lowe’s. How accurate is it and what% is considered
1- burnable but not great
2-Burnable
3-great wood
Obviously on a fresh split.
 
If you're burning in a wood stove/insert, below 25 is considered acceptable.
Split a piece a few pieces open and take some fresh open surface readings. Measure some pine trim you may have around. You'll probably read 15%, measure your palm probably get 35%.
 
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For firewood, those are good enough. I don't know that exact one, but if you read the fine print it is -probably- calibrated for Douglas Fir at 70 degrees F.

I keep my garage at +55dF, so the correction factor to me is to "add one" to whatever number comes up. If the display says 16%, the wood in my garage at 55dF is actually pretty close to 17%.

The most important thing about checking moisture in cord wood is to split a split open and measure with your pins parallel to the grain on the freshly split face. That will tell you how wet the inside is, the outer surface dried down to 16% several weeks ago; that is meaningless, you want to burn the whole thing.

Typically 20% on a freshly exposed face is a good target. You can go a little over that with a lot of stoves, but in practice most likely the sweet spot for your stove in your house with your chimney is probably somewhere between 14-20% MC, you have to get there to find out.
 
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You want 17 percent on a freshly split piece, at room temp.
 
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What if you are testing outside and it’s 90 degrees and humid. Does that throw it off?
Should I bring a piece in the house for a day and then split it and test it?
 
That's right. Summer, or winter, bring that piece inside for a day, then split it and test it.
 
Humidity and temperature has an affect. Best is to have it split and stacked of at least 2 summers in the sun off the ground for hardwoods. Softwoods dry much faster.
The three yr plan (stacked and split off the ground) is the best guarantee for seasoned wood. If you get on this plan you will not need a moisture meter. Unless you forget when your stacks were stacked.
 
ps Those Lowes moisture meters are really good. I have had one for 8 years, very accurate and reliable.
 
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I usually burn 2 year stacked wood. This year was a bit of a tough year with family illnesses. So unlike other years I had to start fresh this year. In December I had 14 cords delivered that I had to process. I split and stacked it all in December. It’s basically oak. I do know it’s drying good. I split a piece outside about 3 weeks ago and measured and it was at 25%. But the test will be measuring it after sitting in my house for the day. I hope this works out.
 
What if you are testing outside and it’s 90 degrees and humid. Does that throw it off?
Should I bring a piece in the house for a day and then split it and test it?


You need to know the species your meter is calibrated for, the species you are testing, the temperature your meter was calibrated for and temperature of the sample specimen.

Once you know what your meter is set up to do, you can then google up some images of temperature compensation curves. The further away you are from Douglas Fir (probably) at 70 degrees F (probably), the more correction you will have to dial in to whatever the meter reading shows you.

All my moisture meter use is at temperatures lower than 70dF, and I always have to add "something" to the number on the screen.

In general, if you split open a split of cordwood and the meter shows you 20% or less on the freshly split face at or near 70 degrees F, your stove is probably going to run just fine.

I am tagging @Woodsplitter67 , he is on the east coast somewhere and has moisture meter experience with hardwoods.
 
What if you are testing outside and it’s 90 degrees and humid. Does that throw it off?
Should I bring a piece in the house for a day and then split it and test it?
Testing at 90 will throw it off. Your better waiting untill the stack is near 70 degrees or bring the wood in the house for 5 hrs or so and then split it and test on the Fresh split face side. This will get you super close.. What species of wood did you get delivered
 
I personally stay away from oak unless I have 3 yrs to stack it and forget it. I've had it for 3 yrs and it still wasn't below 25%. I now split oak very thin.
 
I might be forced to burn it as it is in October. I am feeling that within the next 6-8 weeks I’m going to be at least 25% to 20%. Hoping for the best.
 
I personally stay away from oak unless I have 3 yrs to stack it and forget it. I've had it for 3 yrs and it still wasn't below 25%. I now split oak very thin.

There's no reason to stay away from oak.. its the best wood available in our area. Oak is ready to burn in 18 months if the set up is correct. All of my wood is in wood shedss my sheds are facing summer Prevailing winds. split size varies from 3 to 5 inches.. Once split it goes right in the shed.. I split in winter.. like January/February.. so wood thats split say jan of 18 is ready to burn oct of 19.. 2 full summers of drying and never touched by rain... or there's using a kiln.. and if properly done.. will be dry in 5 monthe..
 
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Don't turn your back on oak. It is some of the best firewood you can get.
I am getting green oak down to 17 percent in 8 months in my non ventilated wood shed. I keep the door closed.
 
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I brought 3 pieces of oak into my house this morning. Each piece was between 6” wide to 4” wide. They sat in my house for about 8 hours. I just split them and tested the moisture with my meter and my highest number was 18.3% moisture. I’m hoping it’s not a goof. I went out back and burned a couple pieces in my fire pit and no water boiling out the sides. I think my worries are over. Yes?
 
I got the yellow meter from lows 4 years ago, I bought it as a novelty item because of this site, honestly I thought I would just test a few pieces for peace of mind then to the back of the tool box it goes.
Well not so much, cause I like to occasionally test a few splits here and there, then there's the occasional phone call from a friend that asks me to stop by and check there stove cause its not working right, or the firewood purchase gone wrong issue (happens at least twice a year to a friend, even after all the drunk banter about dry wood through out the year)
Anyway with that meter you have to be a little careful with the prongs since it metal mounted to plastic, also you want to go in on a freshly split room temp piece with the grain of the wood.
Generally speak 22% is about the highest threshold for burning, anything above that makes a mess of the chimney, and has a reduced heat output.
I generally try to stay between 15-18% on my wood splits, but I'm a head 3 years so its easier for me.
 
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I just bought this meter and tested it on fresh split wood (bigleaf maple, doug fir, white oak and sweetgum). I cut the trees last fall and winter, spit immediately and piled up (not stacked) in my barn. It gets very hot in the summer and has no doors so the breeze flows right through. It's virtually all at 14-18%. I cut a big fir a couple weeks ago (I had to quarter it just to get in the truck) and split it that day. It's reading right around 20%. Is this even possible? For comparison the timbers in the barn are 20%, it's been raining a couple weeks. Some dry lumber in the shop (heated, enclosed) is reading 7-8%.
 
You got to take a near room temp peice (65-70 deg f wood split) re-split it and then test the fresh face.
 
Yes I did a fresh split, with the wood grain. Looked up the temp correction it's +1% to +2% at 15% meter reading so it would only go up at most to 22% if I did it indoors. I'm just puzzled why virtually all the wood I have from split 18 months ago to split last week is under 20% and theoretically burnable. Not that I would burn the wood I'm cutting now before next Nov.
 
Update: I searched around the net and found more than 1 review that stated the reading never goes over about 20% for firewood, even freshly downed and split wood. I'm still trying to get a reasonable reading, but for now all I can say is you get what you pay for. Will be returning it if I can't get a reasonable reading. Still looking for a recommendation for a meter that actually does what it says it does.
 
I got a red and black one at Menards for $14 that seems reasonably accurate. Seen readings from 14% up to 49%. At 50% or over it reads 0L. Freshly cut dead trunks are usually 40-45% and the branches 28-35%, which seems reasonable.
 
I have the Lowes meter for about 30 bucks. Fresh cut wood I am getting 35 to 40 percent. No problem for it to read over 20 percent.