Firsts and Seconds (FAS) - The best and most expensive grade. Boards 6" and wider, 8' and longer. Yields 83-1/3 percent of clear face cuttings with minimum sizes of 4" x 5', or 3" x 7'. Suitable for fine furniture, cabinetry and applications where clear, wide boards are needed.
Selects - Face side is FAS, back side is No. 1 Common. Boards are 4" and wider , 6' and longer. Yields 83-1/3 percent clear face cuttings with minimum sizes of 4" x 5', or 3" x 7'. A cost effective substitute for FAS when only one good face is required.
No. 1 Common - A typical thrift or "shop" grade. Boards are 3" and wider, 4' and longer. Yields 66-2/3 percent clear face cuttings with minimum sizes of 4" x 2', or 3" x 3'. Provides good value, especially if relatively small pieces can be used.
No. 2A & 2B Common - Boards are 3" and wider, 4' and longer. Yields 50 percent clear face cuttings 3" and wider by 2' and longer. Suitable for some paneling and flooring applications.
Sound Wormy - Same requirements as #1 Common and better but wormholes, limited sound knots and other imperfections allowed. Not commonly available.
No. 3A Common - Boards are 3" and wider, 4' and longer. Yields 33-1/3 percent clear face cuttings 3" and wider by 2' and longer. Economical choice for rough utility applications:, crates, palettes, fencing, etc.
No. 3B Common - Boards are 3" and wider, 4' and longer. Yields 25 percent clear face cuttings 1-1/2" and wider by 2' and longer. Applications same as No. 3A Common.
---Softwood Grading
No. 1 (Construction) - Moderate-sized tight knots. Paints well. Used for siding, cornice, shelving, paneling, some furniture.
No. 2 (Standard) - Knots larger and more numerous. Paints fair. Similar uses as No. 1.
No. 3 (Utility) - Splits and knotholes present. Does not take paint well. Used for crates, sheathing, sub-flooring, small furniture parts.
No. 4 (Economy) - Numerous splits and knotholes. Large waste areas. Does not take paint well. Used for sheathing, sub flooring, concrete form work.
No. 5 (Economy) - Larger waste areas and coarser defects. Not really paintable. Applications are similar to No. 5.
A Select - No knots, splits, or other visible defects. Used for fine furniture, exposed cabinetry, trim, flooring
B Select - A few, small defects but nearly perfect. Used for fine furniture, exposed cabinetry, trim, flooring.
C Select - Small tight knots. May be nearly perfect on one side. Used for most furniture, shelving, some trim and flooring.
D Select - More numerous "pin" knots and other small blemishes. May be used for some furniture, shelving, some trim and flooring.
---Plywood Ratings
Veneer Grade Characteristics
N - Smooth natural finish select heartwood or sapwood veneer, free of open defects. This grade does not allow more than six wood-only repairs per 4 ft. x 8 ft. panel. Grain and color must be well matched.
A - Smooth paint-grade veneer; may be used natural for less demanding applications. No more than 18 repairs per 4 ft. x 8 ft. panel.
B - Solid surface veneer. This grade allows tight knots (no more than 1 inch. in diameter), round repair plugs and shims. Permits repairs of minor splits.
C - Plugged Upgraded "C" veneer
Splits limited to 1/8 inch max. width. No knotholes or borer holes permitted larger than 1/4 x 1/2 inch. Synthetic repairs permitted, as well as some limited broken grain.
C - This veneer can have tight knots up to 1 1/2 inches in diameter, and knotholes up to 1 inch across the grain, or up to 1 1/2 inches if the total width of knots and knotholes is within specified limits. Wood and/or synthetic repairs allowed. Discoloration and sanding defects which to not impair strength are allowed.
D D - This grade allows knots and knotholes up to 2 1/2 inches width across the grain as well as limited splits and stitches, and is limited to interior or Exposure 1 panels.
---Exposure Ratings
Exterior
Fully waterproof bond. Designed for applications where panels are subject to permanent ongoing exposure to moisture.
Exterior - Exposure 1
Fully waterproof bond, but not intended for permanent ongoing exposure to moisture.
Exterior - Exposure 2
Interior type with intermediate glue. Intended for protected applications where only slight exposure to moisture is likely to occur.
Interior 2
Designed for interior applications only.
Article provided by Chris Messier - Messman