Tile can make a stunning addition to any kitchen backsplash, providing an eye-catching focal point and sleek, easy-to-clean surface. However, tiling over an existing granite backsplash requires some special preparation and techniques to ensure proper adhesion and a professional result. With careful planning and the right materials, tile can be installed directly over granite to create a fresh new look without removing and replacing the entire backsplash.
Assessing the Existing Granite Backsplash
Before starting a project like this, it’s important to fully assess the existing granite backsplash to determine if it’s suitable for tiling over. Here are the key things to check:
Condition of the Granite
Examine the granite closely to ensure it’s in good condition with no cracks, chips, or flaws in the surface. Any damaged areas of the granite should be repaired or replaced before tiling. The granite also needs to be fully secured to the wall.
The granite should be thoroughly cleaned to remove all dirt, grease, soap scum, and other residues which could interfere with proper tile adhesion. Use a granite-safe cleaner and rinse well.
Seams and Joints
Check any seams and joints in the granite to make sure they are sound. Joints between granite slabs should be filled and level for the best tiling results.
Look at the size and layout of the backsplash. Be sure the design and granite dimensions will work with the tile design plans. Make notes of any outlets, switches, or obstacles.
Smoothness and Gloss Level
The granite surface must be smooth, flat, and free of defects for tiling. A honed or matte finish granite will provide better grip for the tile adhesive than a highly polished surface.
Thoroughly examining the existing backsplash first allows you to determine if modifications or repairs are needed before tiling can begin. This prevents problems down the road.
Choosing the Right Tile
Once the granite is assessed, it’s time to choose the tile. Keep these tips in mind:
- Tile material – Ceramic, porcelain, or natural stone are all good options. Select tile rated for walls/backsplashes.
- Tile size – Smaller mosaic tiles are better for going over an uneven surface like granite. Larger tiles may require more subsurface preparation to flatten the granite prior to tiling.
- Tile finish – A tile with a textured face or mesh backing will adhere better than very smooth glass or porcelain.
- Grout lines – Small grout lines are best. 1/8 inch is ideal. Large grout lines don’t always conform well over uneven surfaces.
- Tile color – Choose a tile that complements the existing granite color. Bring granite samples when selecting tile.
- Waterproof tile – This is a must for kitchen backsplashes. Look for waterproof porcelain or ceramic tile.
Selecting the right tile for the surface and design aesthetic will give the best end result.
Preparing the Granite Surface
Preparing the granite properly is one of the most important steps in the process. The granite must be:
Use a specialized granite cleaner to thoroughly clean the surface. This removes any dirt, grease, soap scum, and old caulk. Rinse well and let fully dry.
Sanding with 400 grit sandpaper gives the granite some texture and “tooth” for the adhesive to grip. Be careful to keep sanding even and uniform.
Apply a specialty tile-bonding primer to the granite. This gives maximum adhesion. Let the primer fully cure per product directions before tiling.
Proper prep removes any bond-breakers and enhances the adhesive grip. Don’t skip these crucial steps.
Choosing the Right Adhesive
The adhesive is what bonds the tile to the granite surface beneath it. Using the proper type is critical for success:
This adhesive works best for directly applying tile over an existing non-porous surface like granite. Look for a thinset rated for bonding tile to surfaces like glass and metal.
A 100% solids epoxy provides extremely strong adhesion. Epoxies are more expensive but provide the best bond, especially for large-format tiles.
Convenient but doesn’t offer the strongest bond. Use for very small mosaic tiles only. Not recommended for larger tiles.
A latex-modified or epoxy thinset is the best choice for a super-strong bond when tiling over granite.
How to Apply the Tile Adhesive
With the right adhesive on hand, here’s how to apply it:
Use a notched trowel
Apply adhesive using a notched trowel to evenly comb it onto the surface. This ensures proper coverage under each tile.
Apply in small sections
Work in sections of 4 to 6 square feet at a time. Don’t spread adhesive over large areas, as it can dry out before tiling.
Use the adhesive’s instructions
Follow all guidelines for open times, skinning over, and wetting the surface before applying tile.
For maximum adhesion, also spread a thin layer of adhesive to the backs of tiles just prior to placing them.
Carefully applying the adhesive provides maximum contact and strength. Don’t rush the process or take shortcuts.
Tiling Techniques and Tips
Here are some key tips to employ when installing the tiles:
Work from the bottom up
Start tiling at the lowest point and work upwards. This avoids dripping thinset residue and allows gravity to help.
Use tile spacers
These plastic spacers keep tile joints uniform. Remember to remove them later.
Check bonds frequently
Periodically lift a tile and check the back to ensure at least 80% thinset contact.
Clean as you go
Wipe away any adhesive residue immediately so it doesn’t dry on the tile surface.
Work in small sections
Completely tile 4 to 6 square feet areas before moving to the next section.
Proper process and techniques prevent problems down the road. Take it slow and check bonds frequently.
Grout fills the joints between tiles. Follow these tips for success:
Let adhesive fully cure
Allow the thinset to cure for at least 24 hours before grouting tiles. This prevents the grout disturbing the bonds.
Grout small sections
Work in 3 to 4 square foot areas. Don’t grout large expanses at once.
Use a grout float
Hold it at a 45 degree angle to force grout into joints. Move diagonally across tiles.
Only mix grout to a semi-dry or peanut butter consistency. Too much water weakens grout.
Wipe and scrub off all grout residue. If it dries on the tile, it can stain the surface.
Sealing with a penetrating sealer prevents stains and makes ongoing maintenance easier.
Good grouting technique prevents problems and creates a pro-quality finished product.
Curing and Ongoing Care
Here are final steps for finishing the installation and keeping the tile looking its best long-term:
Allow a minimum 48 hour cure time before using the backsplash. This prevents movement or damage.
Seal the grout and tile surface with a penetrating sealer every 1 to 2 years to prevent staining and damage.
Always use a pH neutral cleaner for ongoing cleaning. Harsh cleaners can eat away grout or etch the finish.
Re-caulk perimeter joints every 2 years or as needed. Check for any cracks in caulk and recaulk promptly.
Avoid putting excess weight or pressure on backsplash tiles. Don’t cut directly on the tile surface.
Following good curing, sealing, and maintenance practices keeps the tiled backsplash looking fantastic for years to come.
Some common questions about installing tile over granite backsplash:
Can any tile be used over granite?
Smaller tiles with textured or mesh backing adhere best. Porcelain, ceramic, mosaic, and natural stone are good options. Avoid large format tiles and very smooth glass or porcelain.
What about adding Ditra or backerboard over the granite first?
This is not necessary as long as the granite is in good condition and proper adhesives for non-porous surfaces are used. Backerboard adds cost and thickness.
Is fabricating new pieces of granite to match better than tiling over it?
Replacing sections or the entire backsplash with new granite can be extremely expensive compared to tiling. Tiling also allows totally changing the look.
Should sanded grout or non-sanded grout be used over granite?
Either type works, but non-sanded grout is easier to fully clean off the surface of textured granite. Sanded grout can get trapped in dips.
How soon can I use the backsplash after tiling?
It’s crucial to allow a minimum 48-72 hour cure time before regular use. Early heavy use can compromise the bonds while adhesive fully cures.
Installing tile over existing granite backsplash can give a kitchen a fresh new look while being much more economical than replacing the entire granite backsplash. With proper planning, materials, and technique, tile can adhere strongly and look beautiful over granite. Pay close attention to thorough surface preparation, utilizing high-quality bonding adhesives, careful tile installation, and conscientious grouting and curing. The result will be a stunning new backsplash that hides the existing granite for a completely updated look. With some effort and care, you can achieve a magazine-worthy kitchen backsplash without needing to start right from the studs.