Air-dried oak for casework?
Air-dried lumber needs to live in the environment it will inhabit prior to fabrication. 1998.
by Professor Gene Wengert
Is my air-dried red oak safe to use for casework (book cases, pantry cabinets,etc.) or am I courting disaster? Logic seems to indicate that wood, regardless of the drying method used, will eventually reach a state of equilibrium with regard to the environment in which it is placed. Several texts and magazine articles have not given me a satisfactory answer to this question. I would appreciate any light you can shed on this matter.
Your air-dried lumber in the barn will be at 11 to 12% MC (equivalent to slightly under 65% relative humidity in the barn). In the house, you will likely have a humidity of 30 to 40% RH, which will result in 6 to 7% MC in the wood. Oak is a high shrinking wood (3% MC change equals 1% shrinkage). The basement may actually be dry enough to reduce the MC to the 6 to 7% MC level--is it heated and dry? If the basement isn't dry enough, how about putting a few pieces in the attic for a month? (Not too many pieces or you'll crash the roof down!) It is hot and dry in the attic.
Special note: Kiln drying at temperatures over 130F does two things, in addition to rapid drying--it kills all insects, eggs, and fungi in the wood and it sets the resin in softwoods so the resin doesn't drip or flow at room temperature much, if at all.
Professor Gene Wengert is Extension Specialist in Wood Processing at the Department of Forestry, University of Wisconsin-Madison.
Click on Wood Doctor Archives to peruse past answers.
If you would like to obtain a copy of "The Wood Doctor's Rx", visit the Wood Education and Resource Center Web site for more information.
Would you like to add information to this article?
Interested in writing or submitting an article?
Have a question about this article?
Have you reviewed the related Knowledge Base areas below?
KnowledgeBase: Lumber & Plywood: Storage
KnowledgeBase: Primary Processing: Air Drying Lumber
KnowledgeBase: Wood Engineering: Wood Properties
KnowledgeBase: Knowledge Base
All rights reserved. No part of this publication may be reproduced in
any manner without permission of the Editor.
Review WOODWEB's Copyright Policy.
The editors, writers, and staff at WOODWEB try to promote safe practices.
What is safe for one woodworker under certain conditions may not be safe
for others in different circumstances. Readers should undertake the use
of materials and methods discussed at WOODWEB after considerate evaluation,
and at their own risk.
335 Bedell Road
Montrose, PA 18801
Copyright © 1996-2013 - WOODWEB ® Inc.