Using Air-Dried Lumber for Furniture
There are risks, but some say it can be done. April 19, 2006
I have read that lumber can be used for cabinetry work after lengthy air drying. Is this true?
(Sawing and Drying Forum)
From contributor W:
Only if you can air dry to 6-7% mc and you don't have a bug problem.
From contributor C:
May be pitch will be an issue in pine, as it will not have been set by high temps.
From contributor I:
General answer - yes, you can. As the previous posters have mentioned, there are a couple of potential problems. You have to make sure that you don't get insect infestations, there may be unset pitch in some softwoods, and you usually have to complete the air drying inside to get the wood completely dry. Some woods are easier to air dry (like cedar), and some prefer to work with air dried walnut, etc. Worth considering that people have been making furniture for hundreds (or thousands) of years without kilns. Of course, they didn't mind waiting a few years for wood to season.
From Professor Gene Wengert, forum technical advisor:
If you read the previous posting carefully, you see (and it is true) that you cannot use air-dried wood for furniture, flooring, cabinets, and similar indoor projects unless you dry it to a lower MC than you can achieve in air drying. In air drying in most of the USA and Canada, you can only achieve 15% to 12% MC. However, wood inside a heated home or office is 6% to 7% MC much of the time. So, you need to dry the wood further. A kiln with its heat offers rapid, safe drying that also kills any insects and sets the pitch in softwoods.
From contributor B:
For the questioner's sake, I would like to add some clarification to the term "air dried." I believe Dr. Wengert is defining "air dried" as lumber that is dried to the lowest MC that it can obtain outdoors, which in my area is around 12-14%. I have been using air dried lumber for 15 years to make cabinets and furniture as a hobbyist. When my "air dried" lumber reaches its lowest MC outdoors, I bring it into my heated shop for at least 2 months before I am going to use it. During this time, it dries down to 8-10% moisture. The furniture in my home holds to around 8-10% moisture, so I have effectively "kiln dried" it to be in equilibrium with my home conditions. This is how I am able to use air dried lumber that has not been truly sent to a kiln. A kiln is definitely necessary to kill bugs and set pitch in pine.
From contributor R:
Gene, I have not had cause to question any of your tremendous advice in the past, but must disagree with your answer here. I have built many pieces of furniture with air dried wood. Most of it measured 12%, and have had no failures. The oldest piece I made was a walnut hutch that was built in 1983. I pay great attention to how the furniture is built. I know the wood will shrink, so no thick slabs, lots of frame and panel work with special care so that no glue makes it to the panel, no cross grain construction, no plywood except for panels, no wild grain in door frames (only quarter sawn in door frames), finish both sides of the stock equally, all the bells and whistles of good construction. It also wouldn't hurt to build a complicated piece in the summer so it won't be slammed with dry air from the winter. I feel there is no comparison for the look and clarity of the wood with air dried - it is far superior to kiln dried. And much easier working as well. Now, bugs are a different story.