Plywood 101 Plywood 101
Whenever a DIY project is on the agenda, one of the first materials many property owners purchase is plywood. This manufactured product comes with many benefits. There are also several disadvantages, but depending on the project, these may not be a deciding factor. We outline everything you need to know as a consumer about plywood below. Once you’re ready to get started, visit the home improvement center. Discuss the project with a sales representative to ensure you have the right type of plywood for your project.
Plywood board is an engineered wood product using thin layers of wood, usually two to three pieces, that's cut using either a flat or rotary method. Each wood layer, also referred to as ply or veneer, uses a variety of materials and is held together with a bonding agent. The adhesive used depends on whether the material is for interior or exterior surfaces and if the plywood is softwood or hardwood. The method in which the plywood is placed layer upon layer with the grain of the wood aligned perpendicular to each other makes the material stronger than steel, warp resistant, and less prone to cracking, swelling, and shrinking.
Plywood comes in various sizes to meet the needs of a variety of projects. It's available in sheets measuring in a choice of 1/8”, ¼”, 3/8”, 1/2”, and ¾” thickness. Large, flat plywood panels used in construction eliminate wasted material versus traditional log cutting, and are used in projects such as the installation of subflooring, bowling alleys, and pianos. Smaller pieces can be used in other projects such as furniture making, decorative items, ramps, wall paneling, shelving, ceilings, and even airplane propellers.
Hardwood plywood is available from several sources such as mahogany, oak, ash, teak, maple, cherry, and birch. Softwood plywood includes redwood, cedar, spruce, and pine, with Douglas fir considered the most commonly used material. Plywood can also be made by combining both hardwood and softwood. While the U.S. provides plywood, the material is also imported.
Plywood is rated either A, B, C, or D. A and B are the highest in quality, more expensive, and have the lowest number of repaired wood defects. C and D are less expensive, but the panels will have more repaired areas, or the defects left as-is.
Plywood is a popular choice due to the natural patterns and markings of the wood. For added beauty or to enhance the visual appeal of the wood grain, plywood can be stained, providing a finished look to interior and exterior surfaces. Plywood can also be treated with chemicals to help resist wood rot and act as a fire retardant. It's created from renewable sources, making it environmentally friendly.
Depending on the availability of the material in your location, hardwood plywood can be expensive when compared to standard board stock such as particle board. The higher cost is partially due to the manufacturing process, which uses more material per sheet and results in a heavier/sturdier piece of material.
Depending on the project, plywood may not be the best choice due to natural defects. These include pin knots, color streaks, burls, and discoloration. Plywood is also prone to water damage.
Pressure Treated Plywood
To avoid corrosion of metal fasteners or hardware used to secure pressure treated plywood, purchase only those items specifically designed to use with pressure treated plywood materials.
Plywood comes from both U.S. and foreign sources, and there is always the possibility that the actual measurement of the panel won’t be the same as what’s stated on the label. Plywood is manufactured primarily in sheets measuring 4x8 feet. When buying plywood, purchase what you’ll need for the project all at one time and from the same supplier to guarantee consistency.
Treated plywood is no exception when it comes to the dangers of inhalation of wood dust and fumes from chemical adhesives. Always cut treated plywood outdoors, and wear safety glasses and a mask for protection.