Moisture content under tarps unreliable, or am I losing it?

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tabner

Feeling the Heat
Jan 17, 2019
371
Eastern CT
Started out burning this year back row of my woodpile all maple and oak that has been CSS for minimum two years, on pallets under a tarp. However my tarp definitely has some holes as it’s been sitting there for a few years and a tree fell on it at one point.
That first row burned great and moisture content was perfect 16 - 18.
I’m now into the inner rows and I’m getting terrible burns, pulled out the moisture meter and I am getting random and intermittent high readings, with some pieces being over 21%.
Is it possible that rows which weren’t on the outside of the pile, combined with tarp holes, could cause this much of an issue?
It seems like unless you have meticulous tarp care a woodshed is almost necessary?
 
I have the same problem, I got free tarps that have holes and a lot of my wood is not burning correctly (randomly, as you said)
I have been wanting to build a wood shed but the price of lumber dissuades me from doing it.

Now the prices are going back up again lol!

I think people that have uncovered / junky random wood piles are burning it wet in their old stoves, the newer stoves need dry wood
 
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I have the same problem, I got free tarps that have holes and a lot of my wood is not burning correctly (randomly, as you said)
I have been wanting to build a wood shed but the price of lumber dissuades me from doing it.

Now the prices are going back up again lol!

I think people that have uncovered / junky random wood piles are burning it wet in their old stoves, the newer stoves need dry wood
Pallet floor, sides, back and roof covered with a tarp or some junked sheet metal on top can be built cheap. Pallets are available for free at many places.

 
Started out burning this year back row of my woodpile all maple and oak that has been CSS for minimum two years, on pallets under a tarp. However my tarp definitely has some holes as it’s been sitting there for a few years and a tree fell on it at one point.
That first row burned great and moisture content was perfect 16 - 18.
I’m now into the inner rows and I’m getting terrible burns, pulled out the moisture meter and I am getting random and intermittent high readings, with some pieces being over 21%.
Is it possible that rows which weren’t on the outside of the pile, combined with tarp holes, could cause this much of an issue?
It seems like unless you have meticulous tarp care a woodshed is almost necessary?
I had some maple stored that way several years ago. Rainwater settled in dips in the tarp and then funneled down in the rips. And this was in a shady area where the tree came down, so drying was poor. Burning that wood was a challenge and the only time I have had serious creosote buildup. I would have been better off leaving it uncovered.
 
I do the opposite of what many here do. My stacks are all uncovered, and under pine trees in mostly shade. The tarps i tried many years ago seemed to trap more moisture than the uncovered stacks and they would never dry out. So now i leave everything uncovered to season. I have a small roofed area that i'll load up 1/4 cord or so, and a couple hoops that i fill with the most seasoned wood and cover that with clear shower curtains. I also have a small wood room in the house entryway that i keep filled with the seasoned wood, and i keep a day or 2 of wood next to the jotul. Also i'll put a few clear shower curtains on the most seasoned stacks after it's been dry weather for a few days. This has worked fairly well for me with my small property.

Also i'll only stack 2 rows max back to back with a space between them, but i'm trying to not have any back to back stacks.
The airflow is So Key to drying.
 
Normally I stack hardwood outside uncovered for at least a year. Then it gets moved into the shed for final drying.

I like to top cover, but have learned to not let it hang down the sides. Back when we were processing doug fir and locust I would make a cover for the stacked rows by overlapping big slabs of bark, shingle style just on top. That worked out well.
 
I had some maple stored that way several years ago. Rainwater settled in dips in the tarp and then funneled down in the rips. And this was in a shady area where the tree came down, so drying was poor. Burning that wood was a challenge and the only time I have had serious creosote buildup. I would have been better off leaving it uncovered.
I have seen the same: if the tarp is not self-draining (i.e. has puddles), the woven nature of the tarp will let water slowly (i.e. for a long time) drip on the underlying wood.
And wind --> movement --> friction --> holes...

So I built a shed beginning of '21. I chalked the cost up to "Covid stuck at home self-therapy" ;-) (But it was $painful$ indeed.)
 
Tarps are more harm than good. Stack two rows deep 2-3" off the ground in open sunny area. Oak takes 3 yrs depending on size of split. Leave uncovered for first year. Top cover with metal roofing for second year. I burn after second year. I stay away from oak, it takes too long to season. If I get it I split it like a 2x3.
 
Pallet floor, sides, back and roof covered with a tarp or some junked sheet metal on top can be built cheap. Pallets are available for free at many places.


^^^This

I work for a solar installation company so we always have pallets that the solar panels are delivered on. I used one for the floor, one on each side, and one for the top. I actually left the back open so I could stack from both sides and used some of the slats from broken pallets for diagonal bracing. I then used the old metal roofing from when I replaced my garage roof. I'm just into it for the price of some screws and nails.

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Nice thing is you can just keep adding on with more pallets as you get more wood.
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I recently built a woodshed 2.0 double wide with some longer pallets that our bigger commercial 72 cell panels are shipped on. I haven't put the roofing on it yet, but this is going to hold a good amount of wood when finished.
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I keep one years worth of wood stacked outside before it goes into my shed, tarps are great if you know how to use them properly, even tarps with holes.
If stacking on pallets, turn the pallet 90deg so instead of 2 rows you get 3, stack as normal, then on the middle row stack 1ft higher, this creates pitch so rain water or melting snow has a place to run off, not pool and then find a hole to drain into, if you like just doing 2 rows then after you get your height, run a middle bridge rib between the 2 and go from there. Also try to only cover the top 1/3 of the wood, this allows air to enter, with the center ribs air can drain out the front and back which will take moisture with it on windy days.
 
I was anticipating a wood shed in my future but this has definitely increased the urgency of that project. Just didn’t realize what a frustration these small details could be.
I dug around and found a section of good dry stuff and just threw a load of that in and it is much better, so that’s encouraging.
Side note, I also just did my first full N/S load in this stove and I’m a big fan. I think long term I am needing a wood shed and cutting everything 12” long for N/S.
 
I find 12" a drag to stack though. I sometimes get rounds from my tree company, and if the tree was really big (2' dia oak) he cuts them short because of the weight. Foot deep stacks are considerably less stable.
 
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I crisscross stack all the wood I need in a hurry. I was able to get a few cords of red oak from 30% to under 20% stacked in full sun and wind in a little over 13 months. I leave the tarps off all summer and dont start tarping until September or October. I also take the tarps off during stretches of time when the forecast is calling for sun . Crisscross stacking takes a lot more room but it exposes much more of the wood to air/sun. Im a pretty big fan of oak, the heat it provides is amazing.
 
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I tarp during the winter and leave uncovered during our reliably dry summers. Before the first winter rains I tarp to the ground with two layers of thick large brown Costco tarps. I stack the wood, and pull out wood, so that there's a slope to encourage drainage. No moisture issues with my wood.

It is a pain to access the wood in the winter, which I do during dry spells. ( No snow here.) I load up plastic trash bins - Rubbermaid Brute 44 gallon being my favorite- with wood which I keep near my back garage entrance for easy access. ( Trash cans become garden debris collectors in the summer.) If we had regular summer rains, I don't think this approach would work.

Regardless of it working for me, I still want a shed for aesthetics and easier access.
 
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I find 12" a drag to stack though. I sometimes get rounds from my tree company, and if the tree was really big (2' dia oak) he cuts them short because of the weight. Foot deep stacks are considerably less stable.
I do agree with this concern, although if I design my shed accordingly I should be able to incorporate some sort of supports to help.
So is stacking rows tight up against each other pretty much always frowned upon? Obviously this gives the rows a lot more stability and fits more in. But i understand it's not ideal for drying.
 
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If you can add supports (or horizontal 2-3 stack branches bridging the stacks at 2/3 their height), it might work.

However, in my experience, the settling (shrinking upon drying) can still mess up the stacking for short pieces. Especially if they are 4" thick or so, which is my preference.

Or maybe my stacking skills just suck.i prefer 18" stacks and keep 3-4" between them in my shed (with those empty spaces along the direction of the prevailing winds).
 
I'm in Northern RI. Probably similar conditions as you. Had a terrible year for drying. Luckily I have some good dry oak that was sitting from the year before. I am making a shelter this spring to hold 2-3 cords. I burn around 3 a year.
 
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Early on in my wood gathering days I noticed tarps were starting to degrade pretty easily letting water infiltrate through. I switched to rubber roofing take-offs soon after. I needed something that would stand up to the elements long term, as I season my wood a long time before burning it. Burning 6.5 year old stuff now and what I burn will continue to get older as winters go by.

I stack all my wood leaving at least 9" of gap in between all rows to let the air get to both sides of the splits. Is it necessary, I don't know, but it's how I started doing things and has worked out good for me.

Building a wood shed is out of the question for me due to the amount of wood I have.
 
Still struggling with this frustrating situation. At the end of last winter I pulled off a section of tarp and left a full row of this old oak in its own separate, uncovered row. Rather shady part of the yard, but air in front, back, top, stacked up on skids (wooden skids under all my wood). A couple weeks ago I moved the row up against the larger wood pile and covered it with some sheet metal roofing I got (better than tarps). Today I decided to move a couple wheelbarrow loads into the garage into my staging rack. While doing so I pulled about five random splits, split them, and took moisture readings - 19 to 24%!!!! Crazy, most of this wood has been CSS for FOUR years.
Then I went to the back of my yard where I have some pine that has been stacked high, in the sun, covered on top - 14%
I know hardwood is nice, but gosh this is a pain.
I think I’m learning that the WAY you dry your wood may be more important than the length of time, for me anyways.
Next year I’m building a large woodshed / pole barn, and I will have to get much more organized/intentional about my stacking etiquette/details. It seems sunshine is seriously important.
 
If the tarp is fully covering the firewood it can hold moisture it. The tarp should only be on the top, or just leave it off completely and move the next burning season's firewood into the shed in the spring.
 
Same here. I'll be burning 7-8 year old oak this winter. Split/stacked in spring '15. It was 6-7 years old last winter and it tested around that 18% area IIRC. I'm pretty sure it has reached equilibrium moisture though and rises/falls as the climate goes.

I have all my stuff stacked in individual rows on pallets and top covered with rubber roofing. It's in the woods though and doesn't get much sun or wind during summer.
 
For reference this is the pile in question. Several rows deep, more of a firewood cluster, than separated rows. Maybe gets sunshine 15% of the day.
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Sorry to hear about the frustration-we’ve all been there when you figured you have your system rock solid….and then learn differently.
Couple things- you split your wood very big. Drying will be easier if you keep the splits to 6 inches wide or less.
Also, I would just use the tin roofing you already have and lose the tarps. The tin is a great way to top cover. That’s the set up I use.
Try not to be too annoyed. I lost a bunch of good wood that I didn’t take the best care of. I still am trying to get rid of it all for fire pits and whatnot. The learning curve never stops.7917E963-21DF-4A43-870E-E6D33505724B.jpeg
 
For reference this is the pile in question. Several rows deep, more of a firewood cluster, than separated rows. Maybe gets sunshine 15% of the day.
That's top-covered and good. Getting the wood more off the ground would help. Try stacking it on pallets to create a 4" air gap underneath the stacks. The more air that can flow through the stacks the better. If possible, stack them taller with a good-sized gap between the rows.
 
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