Answer: There are several reasons. The first thing that you will find is that both lumber and moldings are thinner than they used to be. Much of this has to do with environmental practices and technology that allow us to get a much better yield out of every tree cut. This drastically cuts down on waste. The second reason pertaining to lumber, is that the “nominal” size, is the size of the wood before it is ripped and planed to clean it up. After this process is complete, the actual dimensions of the lumber will be less.
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