Measuring Moisture Content

[Rick Alger]

Does anyone know of a method or a gadget to accurately measure moisture content in firewood without splitting the wood? I know about testing by the sound of two pieces knocked together, but I am looking for something precise that can indicate the moisture content deep in the middle of the piece of firewood.

[btulloh]

Sounds like you're looking for moisture meter. The inexpensive ones should be fine for firewood.

[Rick Alger]

Thanks for the reply. I should have been clearer. I have a moisture meter. The issue is I have wood stacked and drying that measures around 13% on the outside, but when split it measures around 26% in the middle of a split face. So it's not dry. 

My question is, is there a way to measure that internal moisture without splitting the wood?

[Mike W]

not really, the meters will measure moisture where the pins penetrate, to get the moisture of the core, splitting is your most reliable source i would think.  sure not the answer you were looking for by any means, I would be anxious to hear of others whom can enlighten this as I would be interested in understanding MC within the lumbers core which we mill, not firewood, but same concept.

[SwampDonkey]

Don't go through bark with the pins either. At least the one I have will show the wood green for ever when poked through bark. Different resistance because of density. I'd say split a piece. But 20 % is pretty good for firewood, if in a heated space it will continue to dry during the heating season to. I've got some at 10 %, burns like kindling though. :D I cut my wood in spring time, and stacked under cover in drying racks outside and in a wood room with 1" gaps in the side wall strapping and dehumidifier running to 50% RH. Windows open on cool dry days. The ends are all opened up on my sticks now with checks. Pretty dry, at 18-20 %. Wood is either split or small rounds, so nothing thicker than ~4" from side wall to split face, of course thinner on the rounds since they don't split square.

The meter came with the new furnace along with forearm length, heavy, insulated, wood handling gloves.

[Bruno of NH]

I think the top of the line meters come with a long probe maybe 6" I think

[BluenoseLogger]

You can tell me if I'm wrong but I don't see anything compelling about even pinless moisture meters for measuring dryness of firewood. Pin or pinless all of these meters are only measuring moisture close to the surface.

I'd be really curious to know why a person needs further information about their firewood, after they have already cut and split and properly stacked their wood in good drying locations with proper cover, and let it season for X number of months (or a year or more).

Carpentry or woodworking, different story. I just don't see the value add for firewood moisture measurement.

[John Mc]

You can tell me if I'm wrong but I don't see anything compelling about even pinless moisture meters for measuring dryness of firewood. Pin or pinless all of these meters are only measuring moisture close to the surface. I'd be really curious to know why a person needs further information about their firewood, after they have already cut and split and properly stacked their wood in good drying locations with proper cover, and let it season for X number of months (or a year or more).

I borrowed a friends moisture meter off and on for a couple of years when we first moved in to our new house. It was the first time I had preheated primarily with firewood, and I wanted to get an idea of how long it too to get wood dry enough to burn cleanly and efficiently in our area. I tried a bunch of different storage and stacking conditions. Every so often, I would pull a couple pieces from the stack, resplit them, and check the MC. It was an interesting experiment, and gave me a good idea of how long I need to get my firewood ready to burn under a variety of conditions. It also let me calibrate my other senses so I developed a good idea of how to tell whether the wood was ready (sound, weight, checking of the ends, etc). However, once I went through the exercise, I no longer have any use for a moisture meter, so never bothered to buy one of my own.

I had notes on all of my results, but they were misplaced after years of never referring to them. Wish I had kept track of them, not for my own use, but because it might be interesting to share with others, particularly those just getting in to heating with wood. Fortunately, I remember the gist of the results on comparing various stacking and drying conditions, even if I no longer remember the actual numbers.