Kiln Charge Cooling

Cooling lumber arter drying is not a critical step. June 13, 2014

Question
I have read a lot about red oak kiln schedules and the importance of each step, as well as the importance of proper storage after drying. I have not been able to find much information about the importance of anything to do with the parameters of the cooling down phase. After conditioning is done, how fast is it okay to cool 5/4" RO lumber? Will stresses develop if it is cooled too quickly? Can pushing out a charge too warm counter-act the benefits of the conditioning? At what temperature is it okay to open the kiln doors? If the wood is re-sawn and is flat while still warm (i.e. 120F - 140F), can stresses show up later that are related to running the lumber too warm?

Forum Responses
(Commercial Kiln Drying Forum)
From Gene Wengert, forum technical advisor:
Cooling, after drying is complete, is not considered to be a critical process. In fact, some people have been known to run the lumber into a plant within three hours of the completion of drying. A bad idea, but it has been done. So, open the doors and move the lumber into storage when you are ready.