Our 1" thick and 2"x12" dressed/S4S Pine is either C grade or D grade. Our 2" and thicker dressed S4S is graded #1 Prime. Our Rough Sawn Southern Yellow Pine is #2 or better.

Grade C is our highest grade of pine lumber and is commonly used for fine woodworking and interior trim. The minimum requirements for Select C grade allows for one half inch tight knot per 4 feet of surface area.

Select D grade pine lumber is not as fine in appearance as grade C but maintains a similar level of structural quality. Select D grade allows one tight half-inch knot per 1 foot of surface area.

Just below 'D' and 'C' grade, #1 Prime is the highest grade given for common construction lumber used in framing houses where appearance is important.

#2 grade is suitable for general construction and often used when forming concrete because it is full dimensional and thus larger and stronger than dressed lumber. #2 grade allows for well spaced knots of any quality.

Plywood is graded in quality of appearance from A being the best downward to D. Each side is graded with the face side being the higher graded.

All milled lumber starts as Rough Sawn lumber which then may be Dressed Down to: Smooth 4 Sides or S4S. When measuring Rough Sawn lumber the Nominal Size is the Actual Size: for example a 2x4x16 actually measures as 2"x4"x16'. When measuring Dressed/S4S lumber, which is rough sawn lumber milled down by a molder to make it smooth, the lumber's Actual Dimension is less than its nominal size. The chart below lists commonly sold dimensional lumber in Nominal and Actual sizes.

Nominal	Actual	Actual (Metric)
1" x 2"	3/4" x 1-1/2"	19 x 38 mm
1" x 3"	3/4" x 2-1/2"	19 x 64 mm
1" x 4"	3/4" x 3-1/2"	19 x 89 mm
1" x 5"	3/4" x 4-1/2"	19 x 114 mm
1" x 6"	3/4" x 5-1/2"	19 x 140 mm
1" x 7"	3/4" x 6-1/4"	19 x 159 mm
1" x 8"	3/4" x 7-1/4"	19 x 184 mm
1" x 10"	3/4" x 9-1/4"	19 x 235 mm
1" x 12"	3/4" x 11-1/4"	19 x 286 mm
1-1/4" x 4"	1" x 3-1/2"	25 x 89 mm
1-1/4" x 6"	1" x 5-1/2"	25 x 140 mm
1-1/4" x 8"	1" x 7-1/4"	25 x 184 mm
1-1/4" x 10"	1" x 9-1/4"	25 x 235 mm
1-1/4" x 12"	1" x 11-1/4"	25 x 286 mm
1-1/2" x 4"	1-1/4" x 3-1/2"	32 x 89 mm
1-1/2" x 6"	1-1/4" x 5-1/2"	32 x 140 mm
1-1/2" x 8"	1-1/4" x 7-1/4"	32 x 184 mm
1-1/2" x 10"	1-1/4" x 9-1/4"	32 x 235 mm
1-1/2" x 12"	1-1/4" x 11-1/4"	32 x 286 mm
2" x 4"	1-1/2" x 3-1/2"	38 x 89 mm
2" x 6"	1-1/2" x 5-1/2"	38 x 140 mm
2" x 8"	1-1/2" x 7-1/4"	38 x 184 mm
2" x 10"	1-1/2" x 9-1/4"	38 x 235 mm
2" x 12"	1-1/2" x 11-1/4"	38 x 286 mm
3" x 6"	2-1/2" x 5-1/2"	64 x 140 mm
4" x 4"	3-1/2" x 3-1/2"	89 x 89 mm
4" x 6"	3-1/2" x 5-1/2"	89 x 140 mm

Read below!

Is as the name says and comes full dimensional. Often used for making forms for concrete work.

Lumber that is milled Smooth 4 Sides.

Lumber that is milled Smooth 2 Sides; top and bottom only.

Lumber Eased 4 Sides, the edges are slightly rounded off for used as Decking.

Tongue & Groove with a v-joint and is often used for ceiling board or paneling.

Tongue & Groove with end matching, T&G on the board ends, and is used for flooring.

'Pressure Treated' lumber is a process to force chemical treatment into the wood under pressure to make it termite and rot proof. However, this causes the wood to become wet again and subject to warping and shrinkage as it dries.

'Kiln Dried After Treatment', KDAT is pressure treated or 'PT' pine that is dried again after treatment so it will not shrink or warp like regular PT pine.

Is the recently developed "ever-clear treatment". Clear treatment does not contain arsenic and copper and the associated green tinge found in regular PT pressure treated pine. It still resists termites yet looks natural and is dried after treatment. Clear KDAT pine is very popular for ceilings, paneling, flooring and custom made doors and windows.