Wood Size
The Lumber Industry has an "interesting" way of measuring wood.
When you buy a 2X4 it is (most likely)
really 1.5 by 3.5. This is because
"soft" (example, pine) "green" wood is thicker than
"dry" wood.
This is a
good explanation of how to measure board feet. Another
list of the actual measurements of wood is the size they call it in the store, Actual or
"Dressed" is the real size of
the wood.
My experience with Treated Pine is as follows:
Dressed
Nominal
0.75" X 3.5" = "1 X 4 X (length)"
1" X 5.5" = "5/4 X 6 X (length) Treated Y/P Std/BTR
Decking"
1.5" X 3.5" = "2 X 4 X (length) No 2 Prime PT SYP .40"
1.5" X 7.25" = "2 X 8 X (length) No. 2 Prime PT SYP .40"