How to Install Mosaic Tile

Project Overview
  • Working Time: 3 - 5 hrs
  • Total Time: 1 - 2 days
  • Yield: 32 sq. ft. section
  • Skill Level: Intermediate
  • Estimated Cost: $5 to $20 per square foot

Mosaic tile can be used on floors, walls, countertops, or backsplashes to create intricate designs for sparkle and visual interest. Mosaic tiles do not need to be installed individually. Mosaic tile today comes in the form of multiple tiles pre-attached to a mesh fiberglass backing. This makes mosaic tile far easier to install than if dealing with individual tiles.

White mosaic tile installed with utility knife

The Spruce / Liz Moskowitz

Before You Begin

The substrate (or base) for the mosaic tile must be perfectly flat and smooth. Cement board applied over a plywood subfloor or directly against wall studs is suitable. Mosaic tile can be laid directly on plywood or wallboard in non-wet locations.

To cut cement board, score it with a sharp utility knife, guided by a steel carpenter's framing square. Snap at the score lines. Secure the boards with a gap of about 1/8 inch between boards. Cover the seams with 2-inch wide fiberglass cement board tape and cover with thinset.

What You'll Need

Equipment / Tools

  • Rubber tiling float
  • Notched trowel
  • Tape measure
  • Tile nipper or wet saw
  • Framing square
  • Pencil
  • Utility knife
  • Level
  • Chalk snap line
  • Clean rags
  • Two-by-four scrap

Materials

  • Mosaic tile sheets
  • Thinset
  • Grout
  • Grout haze remover
  • Grout sealer
  • Tile spacers

Instructions

Equipment and Materials for Installing Mosaic Tile

The Spruce / Michela Buttignol

  1. Plan the Tile Layout

    Measure the length and the width of the room. Determine the halfway point and mark this on each of the four walls. Snap a chalk line in each direction to draw intersecting perpendicular layout lines.

    Starting at the center of the tile field lets you install full sheets of mosaic tile until you reach the edges of the field. At the edges, cut the mosaic tile sheets to size.

    White mosaic tile laid down for planning layout

    The Spruce / Liz Moskowitz

  2. Lay the First Sheet of Mosaic

    At the center of the layout lines, spread thinset mortar with the square side of the notched trowel. Work in sections about 2 to 3 feet square. Press the mosaic tile sheet in the thinset.

    Tip

    Do not overapply the thinset. You should be able to see the cement board at the bottom of the grooves.

    Notched trowel setting thin layer of adhesive to apply white mosaic tile

    The Spruce / Liz Moskowitz

  3. Continue to Lay Tile Sheets

    Install adjoining mosaic sheets. Use tile spacers to ensure that gaps between sheets are the same as the gaps between tiles within the sheets. With mosaic sheets, the small tiles are staggered so the sheets interlock. Keep the grout seams uniform throughout the tile field.

    White mosaic tile pressed down in first quadrant

    The Spruce / Liz Moskowitz

  4. Press the Tiles

    Press the mosaic tile sheets occasionally with a clean rubber tile float or with a small piece of wood (about 12 inches square). Do so gently to prevent squeezing thinset out.

    Tip

    Mosaic sheets can ripple or form waves. Pressing equalizes the surface and eliminates waves.

    White mosaic tile set down with metal trowel for even placement

    The Spruce / Liz Moskowitz

  5. Cut the Tile Sheets to Fit

    Approaching the borders, cut the tile sheets by cutting the fiberglass mesh backing. Cut between the tiles.

    Utility knife cutting white mosaic tile to fit edges

    The Spruce / Liz Moskowitz

  6. Cut the Individual Tiles

    To cut individual mosaic tiles, use a wet tile saw, tile nipper, rail cutter, or hand-held angle grinder.

    • Wet tile saw: Slowly feed sheets of mosaic tiles through the wet saw in the same way larger tiles are cut.
    • Tile nipper: A tile nipper, which looks like a pair of modified pliers and can be used to nibble each tile square within the sheet.
    • Tile rail cutter: Use a rail cutter (or snap tile cutter) to score an entire row of tiles. Then, snap the tile apart. Do each tile by itself.
    • Grinder: Cut mosaic tiles with a 4-1/2 inch grinder fitted with a diamond wheel.
    Tile nipper cutting individual white mosaic tile

    The Spruce / Liz Moskowitz

  7. Complete the Remaining Quadrants

    With one quadrant of the tile job done, repeat the preceding steps to complete the other three quadrants, one at a time. With each quadrant, work from the center point of the layout outward to the edges.

    Remaining quadrants of white mosaic tile added to adhesive

    The Spruce / Liz Moskowitz

  8. Install the Trim Tiles

    Install trim or accent tile pieces like bullnose edging, cove tiles, or baseboard tiles. After all the tiles are installed, allow the installation to harden before grouting.

    White mosaic trim tile placed on edge of tile flooring and red wall

    The Spruce / Liz Moskowitz

  9. Mix the Grout

    Mix a batch of grout in a five-gallon bucket. Use unsanded grout for tiles with grout seams that are 1/8-inch or narrower. Use sanded grout where the seams are wider than 1/8-inch. Follow the manufacturer's directions for mixing.

    Unsanded grout mixed in white bucket with electric drill

    The Spruce / Liz Moskowitz

  10. Apply the Grout

    With the rubber float, spread the grout over the top of the tile. Force the grout into the joints by holding the float at a 45-degree angle to the surface. Alternate the direction of the grout float to ensure that the grout fills all joints.

    Tip

    Scrape off large amounts of excess grout from the face of the tiles with the edge of the float.

    Edge of rubber grout float spreading white grout over white mosaic tile

    The Spruce / Liz Moskowitz

  11. Clean the Tile

    Allow the grout to harden slightly, according to the manufacturer's directions, then wipe the face of the tiles with a clean cloth to remove dried grout.

    After the grout is fully cured, remove the remaining grout film with a liquid grout haze remover.

    Yellow sponge with liquid grout haze remover wiping across white mosaic tile

    The Spruce / Liz Moskowitz

  12. Seal the Grout

    Brush grout sealer on the grout after the grout has cured. Sanded tile grout must be sealed to protect the underlayment. With mosaic tiles and their many grout lines, it's easiest to apply sealer by brushing or rolling the entire surface. Wipe excess sealer from the surface.

    Tip

    Most sealers suggest two applications for initial sealing, then an additional application every one to two years.

    Person holding grout sealer

    The Spruce / Liz Moskowitz

When to Call a Professional

Installing mosaic tile is painstaking and often more difficult than laying larger tiles. Controlling thinset seeping through the seams is tricky. Also, it can be hard to keep the tile sheets flat.

Call an experienced tile setter to install your mosaic tile if you have these or other concerns.

The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Grout Joint Size. The Tile Council of America.