It’s the low-cost, low-tech way
to dry lumber. Here’s how to do it right.
By Dave Munkittrick
Want a truly cheap and easy way
Although air-drying is inexpensive
It’s slow. Depending on the species
Air-dry isn’t dry enough for
Loss of material. When you airdry
There’s not much you can do about
Put Your Pile in the Open
Click any image to view a larger version.
1. Box-piled lumber yields the most high-quality boards.
• Straight sides and ends
• Full-length boards on the outside of the pile
• Short boards staggered through the inside of the pile
• Offcuts used as spacers to bridge the gaps caused by short
2. A slanted roof helps the pile shed water.You can do this in a
Prepare a Good
For outdoor drying, the foundation
should be at least 18-in. high. We
used 12-in. cement blocks and 4×6
landscape timbers to keep the bottom
of the pile up off the moist ground
and to encourage airflow through the
bottom of the stack. Level the cement
blocks to create a flat foundation.A
dip in the foundation will telegraph
through your whole stack resulting in
less-than-flat boards. Place the timbers
on 16-in. centers.
Prepare the Boards for
First, trim the ends of the boards so
they are a uniform length. Be especially
careful to remove any existing
checks, because they’ll only increase
during the drying process.
Then, “butter” the ends with a
commercial end-sealer (see Sources,
page 98). The money you spend on
end-sealer will be more than paid back in better quality lumber. Make sure the coating is
thick enough to indent with your fingernail.
You may find some variance in the thickness of your
green stock. Sort your wood so that all the boards in a
layer are within 1/16-in. of the same thickness.
Use Good-Quality Stickers
Stickers create gaps between the layers of wood. These
gaps allow air to flow freely through the stack. Make your
stickers from dried wood.They should be straight-grained
and strong, so they can be used over and over again. Standard
stickers should be surfaced to a uniform 3/4 in. x 3/4
in.Use 2- to 3-in.-wide stickers at the ends of the stack. The
extra width helps slow the rapid loss of moisture at the ends
of the boards and makes the stack more stable. Stickers
should be slightly longer than the overall width of the
stack. It is essential that each sticker be place directly in line
with the one below. This creates a vertical column that
transfers all the weight of the stack to the foundation.
Box-Pile the Stack
“Box-piling” is the best way to build your drying stack
(Photo 1). In box-piling, full-length boards are used on the
outside edges, and shorter boards are placed in the interior
of the stack.Fill the voids at the ends of the pile with offcuts
Put a Lid on It
If your stack is outside, it needs a roof to keep out damaging
direct sunlight and rain. You don’t need anything fancy,
although it’s good to have a slight slope in the roof for water
run-off (Photo 2.) We used chipboard covered with tarpaper.
It’s best if the roof overhangs the pile by 6 in.or more.
Weight the Stack
Weight (rocks, cement blocks, sandbags) will lock the
boards in place, helping to prevent warp and twist as they
dry. Plus, it keeps the roof from blowing away.
Control the Wind
To help minimize the effects of the weather, it’s best to
have a tarp that can be dropped down the sides of the pile.
This offers protection on hot windy days when the drying
rate can be too rapid. This is important with hard-to-dry,
check-prone woods like oak and hickory, especially when
the green wood is above 30 percent moisture content.
After you’ve done all you can to protect the quality of
your air-dried lumber, it’s up to nature.
This story originally appeared in American Woodworker June 2002, issue #94
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