I just got some 2x6x20′. Some of them were fairly dry, others seemed waterlogged. I’ve had problems with other lumber I’ve brought home cracking and warping, so I’d like to try to dry these boards right. Here’s what I’ve done so far:
1. Stacked the boards in the garage on the concrete floor, with 3/4″ stringers every 4′
2. Painted the ends with a sealing primer to slow end evaporation.
3. Loosely covered with a couple of tarps.
About how long to you think typical storebought wood takes to even out enough to not worry about cracking or warping – assuming it’s summer where you are and not very humid?
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
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First of all, buy a moisture meter so you won't be guessing.
1. Stacked the boards in the garage on the concrete floor, with 3/4" stringers every 4'
hopefully not directly on the floor.....make sure the stack is tight or band it in some way to prevent them from taking on shapes of their own.
3. Loosely covered with a couple of tarps.
I'm not sure if that's a good idea. You might slow down the evaporation but you're also taking the chance of rot, especially on the concrete floor.
Norse
paul... often we buy our PT lumber for deck posts a couple weeks in advance.. i put a blue tarp down on the concrete floor
then stack the posts with sticking to allow air circulation.. and enclose a dehumidifier, then cover with more blue tarps...
check it every morning to empty the dehumidifier... when it reaches the moisture level you want .... you're done
this works well with KD lumber that was previousl dried and got wet during storage or treatment... it if the wood was never dried , you will get a lot of warping
I worked in a wood shop where we would air dry a lot of rough sawn green lumber. It was stacked under a building with a stone floor, closed of on each end by only wire fence. The stacks started at least two feet off the ground and were "stickered" with 1" spacers between planks. Then we simply waited, for one year. Some warping did occur. If you started out with kiln dried lumber you wouldn't have to wait as long. I belive kiln dried is down around 7% moisture content, and I think 12% is a good number to shoot for if you have a moisture meter. You say it is quite dry there but I would still keep in mind that concrete can wick moisture up from the earth. Other than that what you are doing sounds okay for low humidity. At some point you will have to remove the tarps, just keep the wood shaded, and borrow a moisture meter. Best of luck.
Drying wood properly is a science, there are lots of variables to consider and without knowing all the details all I can offer is a few basic guide lines. First you need to get them higher off the slab, a foot is about the minimum. Painting the ends with a wax based log sealer would be best as most paints do not shrink with the wood and will soon split open allowing moisture to rapedly escape via end grain casusing further checking. If you have them stored indoors out of the wind and direct sun get rid of the tarps or you risk staining and mold setting in as well as a whole host of other problems caused buy too slow of a drying schedule. Dry wind can ruin a stack of wood in a matter of hours if the moisture content is above 20% so if it's hot and windy close the garage doors otherwise leave them open. Once the wood is down to 12% you are pretty safe in the warping and cupping department as the damage if any has already been done. You didn't mention what species of wood it was or it's final use. Exterior or framing 12% is good, for any interior finish work you should be in the 6 to 9% range.
I'm assuming this is for framing purposes?
Seperate each level with the 3/4" stringers(?)....and give em a week and a half to two without the tarp.
J. D. Reynolds
Home Improvements
Thanks everyone for your advice:
Norse: I had thought moisture meters were too expensive, but I just found one at Harbor Freight for $19. Thanks for the tip. The wood is off the floor via 3/4" sticks. In this climate I'm unlikely to get surface mold or rot - it's desert dry here when the Santa Ana winds blow. I'll try to figure out something to hold them tight.
MikeSmith and JAllenClark: This wood is the basic structural stud you buy at the lumberyard, #2 or better. I'm not sure what it should be predried to, if it is at all. I do know that the whole bundle was wet in the middle and had small cracks on the ends. Getting the wood dry is not the problem, keeping it from drying too fast is! BTW, I put one of the driest pieces on the bottom, anticipating that it might dry slower there.
riverman: This is Douglas Fir I'm using. I had a piece of 22' long 2x6 that was in the same condition as the others when I brought it home a few days ago. It lay on the concrete floor supported about 3/8" off the concrete in the middle of the garage - no covering. In 4 days it started showing small cracks all up and down the length. Not big, but they were many. I returned it and got the others today. That dry air we've had the last few days may have really accelertated drying like you said.
JDRHI: They are to be the bottom joists of my storage space. Still work to be done to them though before that. Thanks for that time frame, it's about what I was hoping for.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
If you are going to use them sometime fairly soon maybe you don't want them to dry out yet. If they don't lose any water they'll stay in the shape they're currently in.
To slow down water loss we stack them tight and cover the entire stack with a tarp wrapped as tight as possible.
Well, they will dry and crack if I use them now. Most of the other stuff I've used has. These pieces will have a higher tolerance, so I want to keep them as pristeen as possible. Plus, I'm shooting for that 50% strength boost of dry wood I've been reading about.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Treating the ends as you've done sounds like a great idea. If you aren't in a hurry to get them dry, then just about anything that keeps them straight with even flow of air, or lack of flow of air, will work.