How to Raise the Countertop Height

Measure the length and width of the tops of the base cabinets. Add 3/4 inch to the width for the overhang along the front edge of the countertops. If you want overhang on either end, add 3/4 inch there, as well.

Order laminate countertops or countertops made of special materials, such as solid stone. Consider how thick the additional plywood countertop underlay is going to make the countertop’s depth, so allow for that as you order trim or front profiles.

Cut 3/4- to 1-inch exterior-grade plywood to the dimensions you determined in Step 1, using a circular saw.

Locate the template that comes with the new sink you are installing. If you are reinstalling the old sink, trace around its outline onto a piece of craft paper to create a template. Cut out the craft paper template 1/2 inch narrower than the sink’s outline.

Place the template on the top side of the plywood where you plan to install the sink. Measure carefully to ensure you have the template in the correct spot. Tape the template in place with masking tape. Trace around the template, and then remove it.

Drill four holes at the inside corners of the sink. Make the holes large enough to accommodate a jigsaw blade.

Set the jigsaw blade inside one of the holes you drilled in the previous step. Start the jigsaw and cut along the line from one hole to the next. Turn the jigsaw and proceed to the next hole. Continue cutting all four sides of the hole away. Hold your hand under the cutout as you cut the last straight line so it doesn’t fall away and cause the wood to splinter.

Check that the tops of the base cabinets are level, using a carpenter’s level. If they are uneven, glue wood shims, using wood glue, to the top of the cabinet walls to level the tops.

Place the plywood on top of the base cabinets. Drill pilot holes through the plywood and into the vertical cabinet walls. Secure the plywood to the cabinets with screws long enough to penetrate the wood in the cabinets at least 1 inch. Space screws approximately 6 inches apart.

Set the new countertop in place to dry-fit it. You might need to remove some countertop material along the back side of the countertop if the wall is uneven. Follow manufacturer’s directions for scribing the back side of the countertop. Depending on the type of countertop, you may need to sand off excess material or trim it off.

Lift the countertop’s front edge high enough to run a bead of silicone caulking along the edges of the plywood. Set the countertop back onto the silicone. The weight of stone countertops holds them in place. Pre-drill holes up through the plywood and into the composite base material of laminate countertops. Secure the laminate countertop by placing screws in these holes.