Plywood is constructed of very thin sheets of wood laminated together to create a thicker, stronger sheet. Plywood may be used as a sheathing in the construction of a home, but the use of plywood in smaller projects also makes sense. Plywood can be used in the construction of a kitchen countertop. Whether using thicker sheets as the framework or thinner sheets as the countertop work surface, your local lumberyard may stock exactly what you are looking for.
Countertops covered in laminate material may have a framework constructed of plywood. You may think that since the plywood framework is going to be covered with laminate sheets anyway, use of a low-grade construction plywood may be acceptable. While some builders use this type of plywood for countertop construction, it may be unacceptable when applying a very thin laminate to it. Construction-grade plywood may have voids or gaps in its surface which may show through the thin laminate material. For this reason, a higher-grade plywood with a smoother surface may make a better choice as a countertop framework.
You may prefer the look of wood grain in your kitchen. A kitchen countertop can be constructed of wood, as long as it is waterproofed sufficiently to prevent damage from wetness. If you cannot afford solid wood, thin plywood can be adhered to a countertop framework in much the same way that sheets of laminate are applied. The key to having a sturdy and waterproof work surface when using thin plywood is the use of a marine-grade polyurethane coating or equivalent, otherwise even minor scratches could penetrate the thin layers of the plywood and compromise its integrity.
If using plywood merely as a framework for the finish work surface to be adhered to, ¾-inch-thick plywood is recommended for strength. Strips of the same type of plywood cut to 4-inch widths should be glued or screwed to the edges of the countertop to strengthen this area, making it twice as thick as the rest of the countertop. Plywood used as a finished worktop surface should be 1/8- or ¼-inch material, which should be thick enough for durability.
If you like the look of hardwood and think this would make an attractive countertop surface, check out the 4-by-8-foot sheets of finish plywood at your local lumberyard. Hardwood plywood is available in oak, maple and birch finishes. The price for this type of plywood is not cheap -- around $50 per sheet in 2011 -- but it is much more cost-effective than a countertop made of solid hardwood.