Domestic Plywood Grade Rules

Face Grades

Birch, Ash, Maple & Poplar: Rotary-Cut, Quarter-Cut, Plain-Sliced

Face Grade A GradeB GradeC GradeD Grade
Pin Knots and Small Burls, Comb. Avg.ANSI10- 4 to 1/4″16- 8 to 1/4″No LimitNo Limit
Conspicuous Burls, Max.ANSI3/8″1/2″No LimitNo Limit
Sound and Repaired Knots in CombANSINo4810
Repaired KnotsANSINo4 to 1/8″4 to 1/2″5 to 3/4″
Mineral StreaksANSISlightSlightYesYes
VineANSISlightYesYesYes
Rough CutANSINoSlightTwo 8″ Areas5% of Panel
Blended Repaired Tapering Hairline SplitsANSITwo 1/16″ x 6″Four 1/8″ x 8″Four 3/16″ x 8″Six 1/4″ x 10″

Red and White Oak: Rotary-Cut, Quarter-Cut, Plain-Sliced

Face Grade A GradeB GradeC Grade
Pin Knots and Small Burls, Comb. Avg.ANSI12-10 to 1/4″24-16 to 1/4″No Limit
Sound and Repaired Knots in CombANSINo48
Repaired KnotsANSINo4 to 1/8″4 to 1/2″
Mineral StreaksANSISlightFew to 8″Yes to 12″
SapANSI5%Up to 20%Yes
Blended Repaired Tapering Hairline SplitsANSITwo 1/16″ x 6″Four 1/8″ x 8″Four 3/16″ x 8″

Back Grades

Back Grade 1 Back2 Back3 Back4 Back
Sound Tight KnotsANSI16 to 3/8″16 to 3/4″Max 16 1/2″-1 1/2Yes
KnotholesANSINoAll RepairedAll 3/8″ 10 to 1Up to 4″
Repaired KnotsANSINo8 to 1/2″NotNo
Sound Tight BurlsANSIYesYesYesYes
Mineral StreaksANSIYes/YesYes/YesYes/YesYes/Yes
Rough CutANSITwo 8″ Dia. AreasYesYesYes
Joints or SplitsANSISix 1/8″ x 12″ Rep’rdSix 3/16″ x 12″ Rep’rd3/8″ x 1/4″ LOP1″ to 1/4 LOP,
1/2″ to 1/2 LOP,
1/4″ to Full LOP