Terra-cotta refers to a group of soft, red clay tiles that typically are handmade. They can be Mexican, Brazilian or French tiles, and may have moderate to extreme variations in color, texture and sizing. Nearly all terra-cotta tiles are sold unsealed. This means no protective barrier has been placed over the extremely porous clay. This enables the tile color to be changed easily through a number of methods.

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Regardless of what final color the tiles are, they must be sealed afterward.

Wood Stain

It is possible to apply a wood stain to the terra-cotta to change the color of the tiles. Depending on the type of terracotta, its porosity and the final color you wish to achieve, you may have to apply several coats. First test the stain on a sample tile, allowing the stain to dry thoroughly between each coat to see the final color change. Once the color has been achieved, allow the tiles to dry, then seal the top coat with a terra-cotta sealer.

Darkening and Sealing

It is possible to darken and change the color of the terra-cotta while sealing the tile. This is a permanent color change and may result in a more traditional color for the floor. A color-enhancing sealer that deepens the natural color of the terra-cotta is one choice. This topical sealer darkens the tiles to the color they appear when wet. It is applied after grouting. Boiled linseed oil also can be used to stain or darken terra-cotta tiles. Apply one or two coats as the tiles are installed to protect them and darken their color at the same time.

Accidental Staining

If you like the appearance of your terra-cotta and do not wish to apply a stain or change the color, be warned that unless they properly are treated during installation, your tiles may stain anyway. Terra-cotta tiles can be stained by water, footprints and grout. Food, foot traffic and day-to-day living also may severely stain the tiles if they are not properly sealed. Seal the tiles as they are laid, immediately prior to grouting, or after grouting if a grout release has been used. Reapply the sealer yearly to help prevent future stains.

Preparation

Before you apply a stain or try to enhance the color of the terra-cotta, make sure the tile is ready to take the new color. Tiles must be clean and dry with no existing layer of wax or sealer in place. If this is a new, just-installed floor, it can be stained or sealed immediately. If it is a floor that has been done for a while, apply a terra-cotta stripper to its surface. This removes any wax, previous impregnating sealers that did not affect its color, or any color-enhancing sealers that have faded or were undesirable in their finish. When the stripped tiles have been rinsed and completely dried, apply the stain or enhancer. Tiles appear lighter in color when they are dry.