How to Install Terracotta Tiles

STEP 1.1 Inspecting and Preparing Tile

Make sure to inspect your tile upon its arrival. Take photos of the delivered freight, and note any damage on the driver's documents before you sign for it. Store the tiles inside, in a clean, dry place. On installation day, make sure to set up multiple boxes, so that tiles can be examined, cleaned, and set in a rotation. This helps disperse slightly lighter or darker tiles harmoniously through the installation. Make sure to determine the "face" of the tile, when examining each one. The face is typically smoother than the back, and a face-down tile may stand out in the installation.

Make sure you or your tile setter understands the layout before beginning. Some shapes have particular layouts with multiple shapes that must be adhered to, or patterns can be created by alternating different color terracotta tiles. For instance, octagon-shaped tiles typically have a small square referred to as a "key", to fill the voids and complete the layout.

Be sure to clean your tiles, and make sure they are clear of loose dust and clay particles. This is best achieved with a damp sponge, but make sure that the tiles are completely dry before applying sealants, to prevent trapping moisture in the installation.

STEP 1.2 Selecting Sealant

All terracotta tile must be sealed during installation, to improve their long-term maintenance and stain resistance. Make sure to understand and have available the appropriate sealant for your application.

Our Villa Lagoon Tile NanoSealant is an excellent option, and the remainder of this guide assumes that it is the sealant being used.

STEP 1.3 Substrate Preparation

Make sure you have a surface appropriate for tile installation. The surface should be a cement slab, cement backer board, uncoupling membrane, or other product meant to take a tile installation with thinset. The surface should be clean, level, and stable. Any rigid tile or stone installed on a surface that flexes will develop cracks. Make sure that your installation is water-tight. Moisture entering behind the tile can carry salts which are deposited as stains on the surface when it evaporates. This is called "efflorescense". Tiles should not be adhered directly to plywood subflooring, drywall, or painted surfaces.

For fresh concrete slabs, make sure the slab is sufficiently cured. This may take at least 4 weeks under normal conditions. As concrete cures, it shrinks and releases moisture. Shrinkage can cause mechanical stress to the tile installation, and moisture release can cause efflorescense. Uncoupling membranes and other suitable tile underlayments are recommended for new and old slabs, alike. For larger installations, consult your engineer about the need for expansion joints.

If you have transitions to other materials, plan them accordingly. Particularly, ensure that the edge of the terracotta tile installation is water-tight, such as when transitioning to very different materials such as carpet.

Step 1.4 Selecting Adhesive and Grout

Tile adhesive should be regular or modified thinset. Make sure it is a quality product suitable for heavier tiles.

Grout should be a regular, sanded grout, of neutral color for grout widths of 1/4 inch or more. If a smaller grout width is desired, unsanded grout is recommended, but test the layout in a dry run, to make sure the tiles are capable of tighter joints. Epoxy grouts can be more difficult to clean, causing grout haze. We recommend MAPEI Flexcolor CQ grout, as our internal testing has found it to provide superior cleanup versus other products tested.

High-contrast grouts (such as black grout with light tiles, or white grout with dark tiles) are not recommended, as they can increase the likelyhood and noticeability of grout haze. Do so at your own risk, by testing first, and using extreme care.

Many manufacturers will have slightly different mixtures for different situations. Make sure that the products you choose are suitable for the tile, substrate, surface, and grout width you are using.

Step 1.5 Miscellaneous Supplies and Equipment Needed

• Marking and Measuring
  • Level
  • 6-8 Foot Straight Edge
  • Tape Measure
  • Carpenter's Square
  • Pencil
  • Chalk Line
  • A Quarter (or other large coin)
• Tile Wet Saw
  • Diamond Blade
  • Saws can be rented from many hardware stores.
  • Read Directions, and Use Appropriate PPE.
• Prep Tools
  • Sponges
  • Clean Rags
  • Buckets (for water and for mixing)
  • Drill and Mixing Paddle Attachment
  • Wet/Dry Shop Vaccuum
  • Mixing Bucket Dust Collector (WaleTale, Dust Hog, etc)
• Tile Setting Tools
  • Grout Float / Rubber Trowel
  • Notched 1/2" Hand Trowel
  • Tile Spacers
• Personal Protective Equipment (PPE)
  • Goggles / Safety Glasses
  • N95 Respirator, or Better
• Sealant Tools
  • See Instructions for Each Sealant Type

Step 2.1 Layout Lines

In most situations you're going to want the installation centered in the room, so that the rows of tiles along the walls are the same width on opposite walls. Starting with the longest walls, find the center point with your tape measure, and mark it on the floor. Do the same on the opposite wall, and use your chalk line to snape a line between the two points. Then repeat the process on the other two walls, and you should have two lines that intersect at the center point of the room. Check that the lines are perpendicular with your carpenter's square.

Step 2.2 Dry Layout

Now you will likely want to check your layout dry. Without using adhesive or grout, start at the center, and lay the tile out to the wall, using tiles spacers. You can now see how much space is left at the wall. If the space is less than half the width of a tile, you may want to shift the whole section by a half tile, essentially centering the first tile over the center line, rather than starting at the edge. This may not be desired for some patterns and layouts. Repeat the process in the other direction. You will have an "L" of tile from the center, outlining one quadrant of the floor. Double-check that this will give the layout you desire. You may want to measure and snap new chalk lines, if you choose to shift the layout by a half-tile. It's also a good idea to double-check measurements and squareness before moving on.

Step 2.3 Preparing Thinset

Using a modified thinset or unmodified thinset, read the directions from the thinset manufacturer. Make sure that the product is intended for the substrate and tile being used. You will be mixing what is essentially a bag of cement with water. Mixing is typically performed in a 5 gallon bucket, using a mixing paddle attachment with a corded power drill. Make sure to follow the directions for ratio of water and mixing method. Make sure to use a respirator, and even better, a mixing bucket dust collector. These attach to your shop vacuum to help keep the aerosolized powder from drifting around the room. This airborne silica dust is dangerous with repeat exposure, and can cause cancer or lung disease.

Step 2.4 Apply Mortar, and Set Tiles

Work in small sections, 2-3 square feet at a time. To prepare the surface, first "burn in" the thinset by taking a small amount, and pushing it into the surface with the flat side of the trowel. The whole section should be "wet" with a thin smear of thinset. Then take a larger amount, and use the notched side to smooth out bead-rows of thinset. Prepare the cleaned tile by wetting the back side of the tile with clean water, using a damp sponge. Then you'll want to "back butter" the tile by putting enough thinset on the back to press-in a smooth, level layer.

Press the tile into place, using only hand pressure. Tile spacers can do a great job keeping your spacing even, and many are designed to help keep tiles level. If not using spacers, you can use a quarter or similar coin, and slided back and forth from one tile to another to find "lippage". Make adjustments ONLY with consistent hand-pressure. Never use a mallot or other tools with terracotta tile. Even if it does not cause any immediately noticeable damage, the stress can lead to tiny surface cracking later. Try to avoid getting any thinset on the surface of the tile. If you do, clean it immediately, and do not allow it to set in. Terracotta tile stains easily.

Step 2.5 Allow to Cure

Allow sufficient time for the thinset to cure and dry. Typically at least 24 to 48 hours. For best results, test that the installation is dry using a moisture meter. If unsure, try taping down a square of plastic film using painter's tape (other tapes may dirty the tile with adhesive). Allow to sit for several hours or overnight, and look for condensation on the underside of the film.

If you are installing a sub-floor heating system: do not under any circumstance allow the system to be powered on until the installation is cured and dry. Many sub-contractors may want to test their system as soon as the tile is set, so they can move on to the next job. Testing a sub-floor heating system beneath wet tiles can permanently damage your flooring. Powering "on" a sub-floor heating system (even for a brief test) while the tile is still damp can permanently damage your installation.

Protect the tile during this period at all times from other trades, foot traffic, and pets. Tile must be clean and dry before proceeding. Do not use strong acids to clean terracotta tiles. Make sure any products you use are safe for terracotta. Protective products such as Ram Board® should be used if there will be a need for traffic during this time.