|
|
|
| Home » Knowledge Base » Knowledge Base Article | Login | Become a Member | What's New | Site Map |
|
WOODWEB DISCLAIMS any and all RESPONSIBILITY and LIABILITY for the accuracy and application of the information below. Readers agree to evaluate the significance and limitations of the information provided, and accept full responsibility for the application of this information. Read More ... |
|
|
Would you like to add information to this article? Interested in writing or submitting an article? Have a question about this article? Kiln dried: Better than air dried? by Professor Gene Wengert Q.
A.
If you air dry, however, the average outside humidity is 65% RH in almost the entire U.S., summer and winter. This is 12% MC. So, air-dried stock would be 12% MC after 1, 20, 200 years. The problem is with the meter check, which was wrong. (Two ways I know: 1) Air-dried is 12%, and 2) if it was really 7% MC, it would not have cracked badly because it wouldn't have changed MC.) There are two important differences between AD and KD. In a kiln, the wood is usually heated above 130 F, which kills all insects, eggs, and fungi. Second, with resinous softwoods, the heat drives off the resin that would be liquid and runny at room temperature. Kilns have been used when we started to have central heating, which is about 150 years ago. The early kilns had a fire built under the lumber piles. The stacks had spaces between each piece of lumber, creating multiple vertical convection channels or flues within the piles. I have an old book that discusses some of the old techniques. 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. Have you reviewed the related Knowledge Base areas below? 
|
