What's the ideal moisture content of seasoned firewood?

[Paschale]

I've really been burned by a couple of firewood providers with unseasoned wood.  I've decided that this time I'm going to call their bluff and tell them to not bother coming to my house with the wood, because I'll take a sample of the wood from all over the stack with my moisture meter.  I've had more bad than good luck with firewood when I've actually had to buy it.

I'm thinking if it's around 15% or so?  What do you guys considered an average moisture content for acceptably seasoned wood?

[woodmills1]

20% or under

try this, have them give you one red oak piece then resplit it and show them the wet red in the middle

[cheyenne]

Do yourself a favor; Buy it green an cheap & dry it yourself then you'll know what you have.....Cheyenne

[mifirewoodguy]

20% or less, everything Ive read has said the same number... Moisture needs to be checked in the center of the piece and at each end to ensure consistancy.

[John Mc]

My local wood burning guru (he was working on designing high-efficiency, clean-burning wood boilers at one point) also says 20% or less. He did caution us about going overboard on the "or less" part. The wood can be too dry to burn efficiently and safely. Some moisture is desirable.

A question for the drying gurus here: Is it true that the faster you dry it, the larger the moisture gradient is from the ends to the middle of the piece? (I'm thinking of a typical 16" split piece of firewood here.) Will the moisture tend to equalize withing the piece a bit as it stands? If so, does this only happen above freezing temps?

John Mc

[mifirewoodguy]

We've found 15% being ideal depending on the species of wood, although our test havent been real scientific, red oak seems to burn better around 10-12%. Theres alot of studies out there that test the BTU's of different species of wood at different % of moisture.....

[okie]

I don't know how it is done in other parts of the country but in my neck of the woods "seasoned firewood" refers to wood that was cut the winter or early spring before and stacked uncovered.
I dont think I have ever seen a person take a moisture meter to firewood, pick up a seasoned stick and a green stick of red oak and there is no room for confusion. I reckon if you ordered firewood a week after a rainstorm you would still see moisture residual from the rain.
I have heard my MIL complain about wood that I know for a fact was cut a year and a half earlier.

[John Mc]

I don't know how it is done in other parts of the country but in my neck of the woods "seasoned firewood" refers to wood that was cut the winter or early spring before and stacked uncovered.
I dont think I have ever seen a person take a moisture meter to firewood, pick up a seasoned stick and a green stick of red oak and there is no room for confusion. I reckon if you ordered firewood a week after a rainstorm you would still see moisture residual from the rain.
I have heard my MIL complain about wood that I know for a fact was cut a year and a half earlier.

I believe some states have laws saying that to legally describe firewood as "seasoned", it has to be at or below a certain moisture content. I'm not sure how thoroughly that is enforced - I would imagine it's probably only addressed if a buyer complains.

I don't view seasoning as a "yes/no" condition. It's more of a continuous spectrum. How it is staked and stored makes a big difference. A single row, stacked off the ground with the cut ends facing into the sun and prevailing wind will dry much more quickly than multiple rows sacked right against each other, and/or out of the sun and wind.

I've also seen problems with firewood described as being "cut X months/years ago". Some sellers who make this claim really mean the tree was cut then, but it may have been bucked and split last week. That wood will most likely not be well seasoned. Similarly, it won't be in good shape if it was cut and split and left where it lay on the ground.

[cantcutter]

I've also seen problems with firewood described as being "cut X months/years ago". Some sellers who make this claim really mean the tree was cut then, but it may have been bucked and split last week. That wood will most likely not be well seasoned. Similarly, it won't be in good shape if it was cut and split and left where it lay on the ground.

Exactly! If you look at it from an economic standpoint you will understand why it is done this way. If the producer buys the logs or cuts them himself he is tying up money in something he cant sell for 12 months. If he then runs it through the wood processor/splitter at that time he is tying up more money and labor. So to prevent that from happening they get the logs cut and stacked and then don't block and split until it is to be delivered. It saves money and extra handling.

I agree with cheyenne. Buy it a year ahead of time and season it yourself. the moisture meter is not going to prove a thing accept that your firewood supply will head back down the road and that guy will not bring you any ever again. As far as the green/seasoned price comparison goes; if you are buying blocked and split wood either will cost you the same. The only way to buy firewood cheap is to buy it log length, by the truckload, and block and split yourself.

Don't buy into the KD firewood sales pitch. A hardwood 4/4 plank takes 6 weeks to dry in a kiln..... A chunk of firewood cannot be dried in the 2-3 days that they place it in the kiln.

[cheyenne]

Or check with the tree services they may drop it off for free rather than pay landfill fees. There's all kinds of free wood out there. Pallets burn great.......Cheyenne

[John Mc]

Exactly! If you look at it from an economic standpoint you will understand why it is done this way. If the producer buys the logs or cuts them himself he is tying up money in something he cant sell for 12 months. If he then runs it through the wood processor/splitter at that time he is tying up more money and labor. So to prevent that from happening they get the logs cut and stacked and then don't block and split until it is to be delivered. It saves money and extra handling.

I agree it saves money and handling, but 12 months in log length, then block and split just before delivery does not make for good seasoned firewood. Maybe that works in some parts of the country, but not around here. One of the reasons I do my own firewood from start to finish. I know what I'm getting, and if it's not right, it's my own DanG fault.

As far as the green/seasoned price comparison goes; if you are buying blocked and split wood either will cost you the same.

In my area, cut and split with local delivery, Green goes for around $200/cord, Seasoned goes for $300+. I wonder if it's coincidence that the pricing reflects the BTUs you can get out of it if you burn it this season? If the price differential holds, green firewood is probably one of the best investments you can make: where else can you get a 50% return on your investment in one year? (If you keep it more than a year, do you get to treat the increase as a long term capital gain, rather than ordinary income? Watch out... Wall Street may be coming to a firewood market near you ;D)

The only way to buy firewood cheap is to buy it log length, by the truckload, and block and split yourself.

I was going to say it's even cheaper to do it all yourself, from standing tree to firewood. However when I look at what I pay in property taxes on my forest land, and what my equipment cost me, it probably would have been much cheaper to have a load of logs delivered each year. It would not be near as interesting or satisfying, however. (Maybe I'd feel differently about it if I were in the firewood business, rather than just a landowner cooperative effort... on the other hand, if I were in the business, I'd be under-equipped, and losing my shirt over the inefficiencies of my operation as it exists now.)

[John Mc]

Don't buy into the KD firewood sales pitch. A hardwood 4/4 plank takes 6 weeks to dry in a kiln..... A chunk of firewood cannot be dried in the 2-3 days that they place it in the kiln.

I was curious about the KD firewood. There is a real shortage of seasoned firewood around here this year. The big jump in demand caught a lot of the regular suppliers short. A local sawmill has been filling in their slow time by running a few loads of firewood through their kiln.

A friend bought a cord that was run through their kiln on a 5 day cycle. I grabbed a couple of pieces from her because I was curious. Borrowed a moisture meter from a woodworker friend and checked them out. At the end of a 16" piece, the meter was pegged at the low end of the scale (6%). Cut off 2" and retested: still pegged low. At 4" in, it was just starting to read at 7%. In the middle of the piece, it measured 15%. I'm guessing the average moisture content was below 10%. It actually felt too light for the species of wood when you picked it up. It was actually a bit too dry for optimum heating firewood.

I assume they can do it this quickly because they don't have to worry about warping, checking or really anything other than driving off moisture. They cycle and temps are very different from what they use for lumber.