How to Build a Countertop
Two types of countertops are commonly installed in kitchens and baths. Preformed countertops such as granite, stone or composites are built in a factory. This type typically is installed by the manufacturer or dealer. No building is involved.
Standard countertops are assembled on-site with plywood or particleboard, a few miscellaneous supplies and a few ordinary tools. Countertop coverings are subjective to taste and materials and are installed after the countertop is built.
Planning Makes Perfect
Preparation is key to solid, permanent countertop installation. Kitchen and bath countertops rely on cabinets for support. Base cabinets should be screwed together, and to the floor and wall, before countertops are installed. Designs, templates and layout for sinks, stoves and appliance spacing should be well-established before starting on the countertop. Other considerations include wiring and plumbing, which should be in place ahead of the countertop's placement, where applicable. Don't forget to plan the specifics of your backsplash and fascia.
Countertop Core Materials
Laminated or tile countertops typically have cores of three-quarter-inch-thick plywood or particleboard. Particleboard is the product most cabinetmakers or home-builders use for general-purpose countertops. Particleboard is affordable. It provides a slick, flat top for laminate, and it's consistent. Plywood is considered stronger than particleboard, but it's more expensive. It has a rougher finish that works better for tile than laminates.
Face and Backsplash Materials
Materials for countertop backsplash and fascia include three-quarter-inch-thick softwood or hardwood. Use softwood such as pine, fir or poplar if you plan on laminating or adding tile to the backsplash and fascia. Use hardwood if you plan on finishing the fascia and backsplash as natural wood. Finished hardwood fascia and backsplash add accents to match cabinets.
Fitting and Cutting
Cut the particleboard or plywood to fit the cabinets using a table saw or circular saw. Table saws work best. They provide clean, straight edges. Circular saws are acceptable if a straightedge and guide are used. Use a circular saw to cut openings for stoves or ranges, if needed. Cut clean, straight lines using scrap boards clamped to the substrate to guide the circular saw: Openings for ranges cannot differ from the requirements more than a sixth of an inch. If you have a template, use it to draw the sink hole. If not, turn the sink upside down and trace it, cutting it three-eights of an inch smaller than the opening with a jigsaw -- sink holes are a bit more forgiving than range openings. If desired, round the corner on peninsula islands using a jig saw.
Mount the Base
Countertops are built piece by piece on top of the cabinets. Start in one corner against a wall for a basic straight countertop, and work toward the end facing the room. If the countertops have a U shape, start in the center and work toward the ends. Cut the biggest pieces that will fit without joints or seams. If the pieces join together underneath, glue and screw three-quarter-inch pine or plywood underneath across the joint to support it. Nail or screw the particleboard or plywood directly to the tops of the cabinets either by using a drill/driver and 1¼-inch screws or by hammering them down using 1¼-inch nails. After you've nailed the countertop in place, use a miter saw to cut the fascia. Apply glue to the back of the fascia and nail it to the front edge using 1¼-inch nails.
Take precautions to provide adequate support if the countertop design includes an overhanging edge that's more than 6 inches. Nail or screw a second layer of particleboard or plywood to the bottom of the overhang. For even more support, depending on the width of the overhang, add decorative braces underneath. Corbel braces screw to the cabinets on one side and to the bottom of the countertop to provide support for overhangs. Optionally, choose from a variety of designer metal braces if desired.
Laminate Is Likeable
Laminate is a common countertop surface material. Cut laminate sheets into manageable sizes using a table saw, or order them to size. Cut or order the laminate at least 2 inches longer and wider than needed to allow for routing. Use contact cement to bond the laminate to the substrate. Route the laminate flush around the cabinets using a hand router with a flush-cutting laminate bit. Finish off rough or sharp edges with files and sandpaper. If you're using laminated backsplash, you have two options: Laminate a three-quarter-inch piece of wood and attach it around the perimeter, or add a laminate strip directly to the wall.
Tile Is Terrific
Tile countertops add a certain flair to a countertop. They also add value. For tiled countertops, you'll need backer board. Cut it to fit, set it with thin-set mortar and screw it down with 1¼-inch cement-board screws. Add fiberglass mesh, add more mortar and set the tiles.