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How to Install an Undermount Sink and a Granite Tile Countertop

Counter-Seal® is used to provide easier installation of an undermount sink and a granite tile countertop.

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  • Time


  • Price Range

    $500 - $1,000

  • Difficulty

    Moderate to Hard


Step 1: Install the Counter-Seal®

The two pieces will need to be joined together with a 1" lap joint. Clamp a straight-edge to the plywood and make several passes with a circular saw set to about half the depth of the plywood. Follow up with a chisel to make a smooth surface. Use construction adhesive and screws to attach the two pieces together as well as to the cabinets.

installing the counter seal

Step 2: Make a Cardboard Template

Use cardboard to template around the Counter-Seal®. Lay out the tiles, leaving the desired amount of spacing between them and tape the seams of the tiles so they do not move. If you do not have tile spacers, you can use coins. Set the template on the tiles and tape it down. Trace along the template and number the tiles with a grease pencil.

Step 3: Cut and Install the Tiles

Remove the tape and cut the tiles with a wet saw. To mimic the factory edge on the cut tiles, use a variable speed angle grinder to buff the edges. Back-butter the tiles around the sink with a square-notched trowel and set them in place.

set tiles in place around sink

Step 4: Install the Undermount Sink

Run a bead of silicone along the outer rim of the sink. This will add an extra layer of adhesion to support the sink.

Lift the sink and attach it to the underside of the Counter-Seal®. Adjust the sink until it is centered.

installing undermount sink