We carry four grades of plywood: A, B, C and D. The grade refers to the quality and appearance of the plywood’s face and back veneers. A has the highest quality and is the most expensive, and D is the least expensive.
A-grade plywood features a smooth, sanded surface without knots. Any wood defects have been repaired with synthetic filler, so the veneer can be painted. A-grade plywood is ideal for furniture or cabinet doors.
B-grade plywood also features a smooth, sanded surface, but may have more repaired defects up to 1-inch across.
C-grade is unsanded and may have several minor defects that will need to be repaired with knots up to 1 1/2-inches across, discoloration and sanding defects. C-grade plywood should be used when appearance is not important, such as for subfloors or garages.
D-grade is also unsanded with defects that have not been repaired and knot holes up to 2 1/2-inches across, discoloration and sanding defects.
You may also find ratings with two-letter classifications, such as BC. BC-grade is a mix grade plywood with one side graded a B, while the other side is graded a C.
There are five important ratings that convey where and how to use plywood: Exterior, Exposure 1, Exposure 2, Interior and Structural 1. Exterior means the panels have been waterproofed and can withstand inclement weather. Use exterior rated plywood for permanent outdoor structures that will be exposed to water long-term. Exposure 1 means the panels have been waterproofed and can withstand exposure to the elements during construction. However, they are not suitable for long-term exposure post-construction. Exposure 2 means the panels are made with an intermediate glue that is not fully waterproof. These panels can withstand occasional moisture but are otherwise intended for interior use. Interior means the panels are not waterproof and are designed for interior use only. They should not be exposed to moisture. Structural 1 is rated for seismic retrofit work, meaning it is designed to be earthquake resistant. Unless they have a Structural 1 rating, other plywood panels of any width are not suited for seismic retrofitting.
Pressure treated (PT) plywood has been infused with chemical preservatives to protect the wood from rot and insects. The wood is placed in a depressurized holding tank that removes the air and replaces it with a preservative. This process is the best way to avoid harmful rot and insects but does not prevent weathering and corrosion. pressure treated lumber will resist the elements better than untreated due to chemical preservatives added, and so will maintain its integrity in conditions that would cause normal wood to rotWhen working with pressure treated wood, we suggest you wear gloves, eye protection and a dust mask (NIOSH N95) when handling wood. Due to preservatives in pressure treated wood, it should never be burned. Sawdust and scraps should be disposed of in a landfil.
The most common plywood sizes are 4- x 8-feet sheets and 5- x 5-feet sheets. We also carry pre-cut project panels that are available in different sizes that may vary by store. These project panels help eliminate waste, cut costs, and are easier to transport than full-size panels. The most common thickness of plywood is 1/2-inch, but plywood thickness can range from 1/8-inch to 3/4-inches.
Marine plywood is constructed from water resistant tropical hardwood, and as these are naturally water resistant, they make marine plywood better than other types of plywood in situations where moisture levels are higher
CDX Plywood is used primarily by contractors to build exterior walls and roofs. CDX plywood has one side veneer grade “C” and one side veneer grade “D”. The two are bonded together with glue which can withstand a little moisture. The APA would recognize CDX Grade Plywood as C-D Exposure 1 plywood.
The face and back (top and bottom) plies are sanded in the manufacturing process to be smooth and even. Little to no additional sanding is needed. Have a finish-quality appearance and a high strength-to-weight ratio. Typically used where it will be seen, such as for cabinets, shelves and paneling. Strong enough to also be used in structural applications.
Made from compressed layers of wood chips and adhesives. Has an unfinished appearance. Has a strong, consistent density. Usually heavier and less expensive than plywood. May degrade faster than plywood due to moisture. The most-used sheathing and subfloor material.
Made from hardwoods like birch, maple and oak. Plies are glued at right angles to one another, making the plywood very strong and stable. Can be heavier than other types of plywood. Best used for furniture and anything that requires a strong load-bearing frame.
Designed for permanent structures. Strong and inexpensive, but unfinished and not made for appearances. Should be covered by other materials by the end of the project. May not be as weather-resistant as other types of plywood. Marine-grade plywood offers superior protection in wet environments. Can be made from hardwood or softwood. Used for framing, beams, flooring and bracing panels.
Ready-to-use, pre-cut plywood boards designed for quick and easy DIY projects. Various types of wood, ply and plywood alternatives available. Used for planned DIY projects when you know the measurements needed for plywood. Great for beginner DIYers.
Made from heat-pressed wood fibers and adhesives. Stronger than particle board, but weaker than plywood. Has a uniform and smooth appearance that is easily painted or stained. Like particle board, it holds up well against temperature changes but not to water. Most often used for mouldings, cabinets and shelving.
Made from compressed wood fibers and adhesives, sometimes using a mold. Often made from wood scraps and waste, making it less expensive than plywood. Holds up well against temperature changes but will swell when exposed to water and moisture. Edges should be sealed to avoid water damage. Frequently used in furniture construction, which is why it is sometimes also called furniture board.
Plywood panels with a coated writing surface. For use with dry erase markers only. Used to create craft tables or finished markerboards for chore lists, notes, calendars, drawings and more.