Plywood is graded in four grades. From Grade AA to E represent the quality of each face of plywood sheet, with grade AA being the top quality with no defects in face veneer.
Plywood that does not meet the standard for AA to E grades will be considered factory seconds, is sold as shop grade or mill-certified plywood. Shop grade plywood has a large usable portion.
Defects of Shop Grade Plywood
Plywood is a wood based panel made of thin layers of wood, glued together to 4-by-8 foot sheets. Almost any type of defect can make in a sheet of plywood being declared shop grade. This can include damage to the veneers that form either the outside or inside of the of plywood. It even includes plywood damaged in shipping. This kind of damage often occurs in the edges of the sheet.
Types of Shop Grade
Because plywood is rated as shop grade when it has defects, then all type of plywood has a chance to be delared shop grade. This includes plywood of any thickness.
Places to Buy
Shop grade plywood can be found in most home improvement supplier. Because it is a factory production second, it is often found at the manufacturer factory or at outlets near. Price of shop grade plywood is often based on the usable portion of the plywood. A sheet with half usable will be priced around half the price of a good sheet of plywood.
The quality of the sheets of shop grade plywood vary depending on the evident defects. In all sheets, some portion is usable. To use this plywood, cut and discard the unusable portion.