Step 3: Spread thinset mortar

spreading adhesive to install tiles
Photo: David Carmack
«»
Chuck a mixer into a drill and blend the powdered thinset with latex additive—not water—until it’s the consistency of mayonnaise. Let it slake (rest) for about 10 minutes. Mix only as much thinset as you can use in 2 hours.

With the flat edge of a trowel, spread a thin layer of thinset (scratch coat) over a 2-by-3-foot area next to the straightedge.

Before the scratch coat dries, apply more thinset using the notched edge of the trowel. Hold the trowel at a 45-degree angle to the floor and spread the thinset evenly in broad curved strokes, then finish with a straight pass, which ensures the best adhesion. Combing the thinset into furrows allows air to escape as the tile is set.

TIP: When spreading thinset, press down hard so that the trowel makes a scraping sound; the trowel’s notch size should equal the tile thickness.
Ask TOH users about Tile

Contribute to This Story Below

    More in Painting & Finishes

    Tools List

    • straightedge guide
      10-foot straightedge (for aligning tile
    • rubber float
      Rubber float (for spreading grout
    • notched trowel
      Notched trowel (for spreading adhesive
    • rubbing stone
      Rubbing stone (for smoothing cut tile edges
    • drill
      Drill-driver and epoxy-coated screws,
      to secure backerboard to subfloor
    • mason's trowel
      Mason's trowel (for mixing thinset and grout
    • margin trowel
      Margin trowel (for cleaning cured joint lines
    • hand saw
      Flush-cut hand saw (for undercutting trim
    • 16-foot tape measure
      Tape measure
    • tile cutter
      Tile cutter
    • power flush cut saw
      Power flush-cut saw (for undercutting trim
    • tile nippers
      Nippers (for breaking off small pieces of tile
    • carbide tipped scorer
      Carbide-tipped scorer and utility knife,
      for cutting backerboard
    • folding A-square
      Folding A-square,
      for checking squareness of tile layout)
    • wet saw
      Diamond blade,
      used with wetsaw to cut corner notches and curves in tile

    Shopping List

    1. CERAMIC FLOOR TILE

    2. THINSET MORTAR

    3. TILE GROUT

    4. TILE SPACERS

    used to ensure consistent joints



    5. MIXING PADDLE

    used in drill to mix up mortar and grout



    6. KNEE PADS

    7. FOAM SPONGE

    for wiping up grout haze