Can You Install New Backsplash Over Existing Tile?

Installing a new backsplash over existing tile can completely transform the look of your kitchen or bathroom. However, it does require some special preparation and techniques to ensure success. Here is a comprehensive guide on installing a new backsplash over existing tile.

Steps for Installing New Backsplash Over Existing Tile

Inspect the Existing Tile

  • Carefully examine the existing tile for any cracks, damage, or loose tiles. Repair any issues to provide a smooth surface for the new backsplash.
  • Check that the existing tile is well adhered to the wall. Tap tiles to listen for a hollow sound, which indicates a poor bond.
  • Determine if the existing tile is ceramic or porcelain. Porcelain is less porous and requires extra prep work.

Clean and Prep the Tile Surface

  • Clean the existing tile thoroughly with an alkaline tile cleaner to remove any grease, soap scum, or dirt. Rinse well.
  • Sand the tile using 220-grit sandpaper to rough up the glossy surface. This helps the new thinset mortar adhere better.
  • Wipe sanded tiles with a damp sponge to remove dust. Let the tile dry completely.
  • Apply a tile primer or bonding agent to the sanded tiles per manufacturer’s directions. Allow to dry completely.

Select Appropriate Backsplash Materials

  • Choose a backsplash tile that is compatible with the existing tile. Natural stone, ceramic, or porcelain tiles are common options.
  • Select a premium-grade modified thinset mortar designed for use over existing tile. This creates a strong bond.
  • Use grout that matches the color of the new backsplash tile. Unsanded grout works best for narrow grout joints.

Prepare the Backsplash Surface

  • Measure the backsplash area and mark the tile layout on the existing tile using a pencil.
  • Mix the thinset mortar according to package directions. Let it slake for 10 minutes, then remix before using.
  • Apply a thin layer of thinset to the back of each new backsplash tile using a notched trowel.

Set the New Backsplash Tiles

  • Spread a thin layer of thinset mortar on a small section of the existing backsplash.
  • Firmly press the backsplash tiles into the thinset with a slight twisting motion. Use tile spacers for consistent grout joints.
  • Check alignment and make sure tiles are flush, even, and level. Adjust as needed.
  • Allow thinset to cure for 24 hours before grouting.

Grout and Seal the New Backsplash

  • Mix grout according to package instructions and work it into the grout joints using a rubber grout float.
  • Wipe away excess grout with a damp sponge and clean water. Rinse sponge frequently.
  • Allow grout to cure fully before applying a sealant. Use a penetrating sealer made for grout.
  • Seal the grout joints per the sealer’s instructions. This prevents staining and damage.

Tips for Success

  • Use a tile wet saw to cut any specialty shapes or contours needed to fit around outlets, corners, or edges.
  • Pre-seal porous natural stone tiles before installation to prevent staining and simplify cleanup.
  • Avoid putting too much thinset under large tiles. This can cause them to sag before drying.
  • Let thinset and grout cure fully before exposing tiles to moisture or heavy use. Check manufacturer’s cure times.
  • Use caution when handling cut tiles. Wear work gloves and safety goggles to prevent sharp edges from cutting hands and eyes.

Frequently Asked Questions

Can I install a new backsplash directly over existing backsplash tile?

Yes, it is possible to install a new backsplash over existing backsplash tile with proper preparation and materials. The key is roughing up the glossy surface and using a premium thinset mortar designed specifically for bonding to existing tile.

What about removing the old backsplash first?

Removing the existing tile is an option but takes more time and labor. The benefit is it allows inspection of the wall behind the tile and starting fresh with a clean surface. But for many jobs, installing right over the old tile is suitable.

How do I prep glossy porcelain or ceramic tile for a new backsplash?

Glossy tiles must be sanded to provide tooth and texture for the thinset to bond properly. Start with 220-grit sandpaper and sand until the glaze is dulled. Clean well before applying primer and new tile.

Can I use regular thinset mortar or mastic?

No, those products won’t bond well to existing tile. Use a premium-grade, polymer-modified thinset mortar specifically designed for use over existing tile. It provides a much stronger bond.

What about spaces with uneven existing tiles?

Fill any wide grout joints or uneven tile surfaces with thinset mortar to smooth things out before installing the new backsplash. The new tiles need a flat surface for proper installation.

How long does the thinset mortar need to cure before grouting?

Check the thinset manufacturer’s instructions, but most require a 24-hour cure time before grouting. This allows the mortar to reach adequate hardness and adhesion strength before exposing it to grout and moisture.


Installing a new backsplash over existing tile can refresh the entire look of your kitchen or bathroom. With some careful prep work and using the right materials like modified thinset and grout, even beginners can achieve professional-looking results. The existing tile provides a sound base for firmly adhering the new tiles. Just take things slow and let all materials fully cure for long-lasting durability. With some patience and care, you can completely transform your space with a brand new backsplash tile design.