The Stovesonline firewood moisture meter

Save yourself lots of trouble and money with a moisture meter

Here is the Stovesonline firewood moisture meter

A firewood moisture meter is perhaps the most important tool for helping you to ensure that you get the most out of your stove. Your firewood moisture meter can help you make sure that you are getting well seasoned wood, and that your firewood supplier is not repeatedly ripping you off. We all know that some firewood suppliers do not deliver well seasoned wood. The first you will know of it may well be when you notice that your stove isn't giving out any heat, that the window is getting tarred up. And it doesn't just stop there burning unseasoned wood will tar up your chimney (increasing the risk of chimney fire) as well as reducing the life of your stove and chimney. Burning unseasoned wood is inefficient and results in high levels of particulates which is bad for health. In terms of how much heat you get out of your stove the moisture content of your firewood is probably the single most important thing to consider.

Next time you get a firewood delivery take out your firewood moisture meter and, before your supplier unloads, grab a couple of logs, split them in half with your axe or hatchet and take a couple of moisture readings. Ideally firewood should have a moisture content of 20% or lower, a few logs at around 25% isn't too bad as long as most of the load is under that.

To take a moisture reading all you need to do is push the
two pins into your chosen piece of firewood

If the wood is a lot wetter than this then it is not actually firewood: it's a load of chopped logs that will one day be firewood when they have dried out (or seasoned), but it isn't firewood. In this case you should either pay less for the wood and store it up until it is dry, or send it back. This is the only way in which firewood suppliers will learn.

In a forgiving mood I might say that some firewood suppliers are not well aware of the issue, or how to properly season wood. Having recently moved back down to Devon I had to get a couple of loads in to tide us over the first winter (2009/2010 will be no problem).
One of the first loads of firewood was at around 40% moisture when I checked with my moisture meter. When I pointed this out they said that some of the load was freshly felled ash which was "OK to burn straight away" (this is a fallacy: ash does have a low moisture content, but all the ash trees I've ever felled have been minimum 35% moisture, even in the dead of winter - ie they still need seasoning). The other logs in the load had come from trees which were 'seasoned' because the trunks had been lying in their yard for a couple of years (they had only just processed the logs that day). No wonder the wood was wet: it hadn't had a chance to dry. It was only because I had my moisture meter that I knew exactly how wet the logs were, although of course there were the tell-tale signs: no cracks in the end grain and a 'wet' smell.

I now have plenty of seasoning firewood for the winter

Another 1 tonne load I had ordered was at around 35-40% moisture when I used my meter, even though I had gone through the maximum moisture content I was willing to accept with the supplier on the phone. It went straight back, although I did offer to buy the unseasoned logs at a decent discount. When questioned this supplier said it had been a wet winter and it had been hard to season the logs properly. Unfortunately seasoning wood properly and then delivering it basically the job description.....no need to bring out the violins just yet.

Use a moisture meter to gauge how well your firewood is seasoning

You can also use the moisture meter to see how well your wood is seasoning, which stacking techniques work best, etc. When you are processing and seasoning a lot of firewood it really makes sense to do it in the best way possible. I have a small, single log thick, stack of wood on a south facing section of wall and was astonished to see the moisture drop from around 55% when I first felled, cut, and chopped the logs, to around 17% now - all in around 4 months! The wood I have in a larger stack in a barn is still at 25%, but should be down to under 20% for when I'll need it.

Here is the Stovesonline firewood moisture meter with its case.
They are on a nice big piece of burr oak which I use as a chopping
block because it is so hard.

Our Stovesonline moisture meter sits firmly in the hand and has a nice big display, it has a handy zippable case, and comes complete with 9v battery (isn't it annoying when people are too stingy to supply a battery?).
To take an accurate moisture reading you need to measure the moisture on the inside of your piece of firewood: the firewood will be more dry on the outside where the wind and sun can get to it more readily. So split your piece of firewood down the middle, push the two pins on the end of the moisture meter into one of the freshly split faces of the wood (not the end grain and not the outside faces of the wood) ideally near where the middle of the piece was before you split it, and press the Power button. The moisture reading will appear on the screen as a percentage. You can press the Hold button to freeze that reading if you want, and when you are done press the Power button again to switch the moisture meter off. I have tested the stovesonline moisture meter against many other types of moisture meter on the market, including some really posh expensive ones designed for joiners/woodworkers, and it compares very well, giving very similar moisture readings.