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I did a search and it seems like 8% is ideal. However, like a few posters here 14-15% seem to be normal in my garage here. I suppose that should be my target?
 

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Target when they kiln dry is 6-8 but as soon as it comes out of kiln it will start to change to environment. Check a piece of dry wood that has been in your shop for a year- that probably will be your target because that is where it will EMC by itself. If you are in Seattle EMC will be one number- Las Vegas will be another. Hope that helps.
 
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Carpenter & Joiner
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You can microwave smaller pieces of wood to reduce their mositure content :) if ever you needed to do that...
 

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The issue is about your finished work being in a home and going through seasonal changes in humidity. If you start with 14% there is a good chance that the lumber will go closer to 7-8%, particularly in winter heating. This means shrinkage. A table top that is allowed to expand and contract by virtue of it's construction and attachment won't be severely effected, for example. Joinery that can be effected by the movement might loosen, chairs are a good example. It's more a matter of what and how you make something but to greatly reduce the potential of shrinkage and any problems it may cause, lumber around 7-8% is preferred. If you were building paneled cabinet doors with wide stiles and rails with 14% lumber, you can reasonably expect the joints to eventually open. The wood will go down in moisture content but it's not likely to go back to 14% as a finished piece in a home. Cabinet grade hardwoods are normally kiln dried to 7-8%. It's up to the purchaser to store it properly so the moisture level doesn't increase. Construction lumber, like most of the pine boards you see at suppliers, are only dried to 12-14%. That's why this lumber isn't the most desirable for some cabinet and furniture work.
 

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I'm not an expert, but it would seem to me that starting with dry wood and allowing for expansion would be better than trying to allow for contraction. Does anyone with experience have a comment on this theory?
 

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I'm not an expert, but it would seem to me that starting with dry wood and allowing for expansion would be better than trying to allow for contraction. Does anyone with experience have a comment on this theory?
Change of moisture content causes the wood to change dimension, mostly across the grain. Whether this is expansion or contraction, the same change of moisture content is likely to result in the same change of dimension and likely the same force if the movement is constrained. I think allowing for the movement is the same whether gaining or losing moisture.

I think the difference is that wet wood is likely to have a moisture content which is a bigger % difference between starting moisture content and your shop/home environment. Dry wood is likely to have a smaller % difference between its moisture content and your shop/home environment.

Larger % difference means bigger change of dimension.

For the original poster target moisture is that of the eventual place where the piece will be used/displayed. If the house is much lower moisture level than the shop, this should be considered in the design. Wet wood will loose some moisture in the shop, then more moisture in the house.
 

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From a movement standpoint...no. From an exposure standpoint, ie near the sink and getting splashed often...yes.
 
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