Subsurface

• In order to tile a countertop, you will need to install a plywood surface. Use plywood sheets that are at least 3/4" thick and secure the sheet with screws. Check the counters with a level before continuing to ensure that they are perfectly level. Laminate countertops should be removed first rather than attaching the plywood to them.
  
  Extend the life of the countertop by laying a waterproofing membrane on top of the plywood. Top the membrane with cement backerboard and then seal the edges with fiberglass mesh tape to keep everything together.
  
  

Installation

• Mix thinset mortar according to the directions on the package. Spread enough thinset mortar onto the countertop with a large notched trowel to lay two to three rows of tile. Press the tiles into the mortar and use tile spacers to maintain even grout lines. Tiles may need to be cut in order to fit the edges of the counter. That can be done with a ceramic tile saw. When you reach the edge of the mortar, spread enough for another two to three rows of tile and continue the installation. When the entire countertop has been covered with tile, allow the mortar to set for 24 hours.
  
  

Grout

• Remove all of the tile spacers from the countertop before you begin applying grout. The grout for a countertop should be prepared with a liquid latex additive rather than water. That will help make the grout waterproof and more resistant to stains caused by spills. Apply the prepared grout to the counter with a grout float. Spread the grout across the tiles until all of the joints have been filled. Wipe the countertop in a circular motion with a damp sponge to remove any excess grout from the face of the tiles. Rinse the sponge in clean water as necessary during this process. The grout will need to cure for one to two weeks before grout sealer is applied. Grout sealer will provide additional protection from stains. The countertop can be used while the grout is curing but any spills should be cleaned immediately to prevent staining.