How to Make a Laminate Vanity Top

Measure the length and width of your base cabinet. Add at least 1 inch to the width for the front overhang of the countertop, as well as 2 inches to the length. To install the laminate countertop against a less-than-straight wall, add up to 1 inch extra to the width so you can trim, or scribe, the countertop to fit against the wall. If you are installing a tile backsplash that will cover any gap between the wall and the back of the countertop, you don’t need to add the extra inch.

Cut 1-inch exterior-grade, medium density fiberboard (MDF) to the dimensions you determined in Step 1 with a circular saw. Cut two 2 1/2-inch-wide strips of MDF to the length of the laminate vanity top. Attach the two strips to the front and rear of the bottom side of the MDF with screws long enough to penetrate at least 1/2-inch into the MDF countertop. Space the screws 6 to 8 inches apart.

Unroll the laminate material onto a clean, flat surface. Allow it to uncurl for at least eight hours or overnight.

Measure and mark where you need to cut the laminate material on the underside of the sheet. Lay a straightedge along that line. As you hold the straightedge, pull a carbide scribe against the straightedge to create a clean, straight cut.

Set the throat of a laminate slitter tool to the depth you want to cut the edge bands. Cut bands with the slitter for the two sides and the front of the laminate countertop.

Lay the laminate sheet face-up on top of the MDF. Set the edge of the laminate sheet against the front and side edges. Clamp the sheet in place with wood clamps. Go around the edges with a laminate trimmer to smooth them. If desired, hold the trimmer at a slight angle for a more professional-looking edge. Remove the clamps. Hold each of the edge bands in position to check for fit. Trim, as necessary, with the laminate trimmer.

Apply a coat of laminate adhesive with a roller, brush or squeegee. Allow it to soak into the MDF. Apply a second coat of adhesive to the MDF as well as a coat to the back of the cut laminate pieces. Let the second coat dry until it is tacky to the touch. Set the edge bands in place. Secure them in the adhesive with a laminate roller.

Lower the laminate material onto the flat surface of the MDF. Press out any air bubbles with the laminate roller. Work from left to right to push air out toward the back of the vanity countertop as you go. Allow the adhesive time to dry, according to the manufacturer’s instructions.

Locate the template for the sink you are installing in the vanity. Center the template front to back on the countertop and tape it in place with masking tape. Draw around the outside edge of the template onto the countertop.

Drill four holes on the inside corners of the sink opening. Place the blade of a jigsaw into one of the openings. Cut along the line from one corner to the next. Turn the jigsaw at the corner and proceed to the next corner. Continue cutting the entire sink opening. If you are installing a vessel sink, cut the hole for the sink’s drain with a hole saw attachment on the drill.

Place the countertop on top of the base cabinets. If necessary, sand the back edge with a hand sander fitted with 100-grit sandpaper to get it flush against the wall.

Run a bead of silicone caulking along the top edges of the vanity base cabinet. Set the laminate vanity top in place on the base. Secure the countertop with screws driven up through the corner braces of the vanity base and into the MDF material. Make sure that the screws do not protrude through the laminate countertop.

Install the sink and its fixtures per the manufacturers' instructions.