How to Seal Reclaimed Terracotta Tiles

Reclaimed terracotta tiles are a virtually perfect flooring product. Exhibiting unbelievably warm earthy colors, they provide authentic old European and Mediterranean charm to any home. When properly and well sealed, they’ll last a lifetime and easily stand up to heavy foot traffic, as well as the daily exposure to food and liquid spills. Although antique floors made from reclaimed terracotta tiles age gracefully and increase their beauty and character over time, if they are incorrectly or poorly sealed, critical problems can occur and persist through the lifetime of the floor. It is important to protect your investment from problems that can spoil the experience of an antique floor.

Homeowners often wish to improve, enhance and preserve the beauty of their antique flooring. Improperly cared for terracotta floors can become dull or take on a hazy appearance. In extreme cases, some unprotected floors will begin to deteriorate. Proper installation and sealing of the floor with appropriate products will prevent these problems.

Antique terracotta tiles were generally, originally manufactured in past centuries, using simple processes and materials- using clay and volatile components. Modern sealants are often inadequate for these antique tiles and fail to protect them adequately. While modern tiles tend to be more ceramic, reclaimed terracotta tiles have been fired only once in simple kilns-they are very porous and some modern sealants, due to their low viscosity, will actually seep through the tiles and seal off the thin set mortar, causing it to retain moisture. Initially, the tiles look great, with rich warm colors but as the sealer seeps into the tile, the dull, hazy appearance will return. In the worst-case scenarios, some water-based sealants will interact with the volatile materials in the antique terracotta tiles, releasing salts from the clay that will travel to the surface and blossom out in a process called efflorescence. The aftermath of this process leaves a white chalk-like layer that covers the floor. Efflorescence loosens the physical bond of the clay, damaging the tiles. Damaged tiles or complete floor areas have to be replaced.

To seal and finish a reclaimed terracotta floor properly, install the reclaimed terracotta tiles like any regular tile. Be sure that the thin set mortar has minimal moisture content. Reclaimed terracotta tile tends to absorb moisture from the adhesive, preventing it from forming a strong bond. Sanded grout is preferred for reclaimed tiles. A colored sanded grout that blends with the tile makes grouting easier. Avoid the use of grout products with pre-sealer. Trapped moisture from these products can create unforeseen reactions that harm your floor. Grout small sections at a time to allow moisture to escape. Upon completion of grouting, clean the floor with water or a mild acid solution and let the floor dry completely over a period of two weeks allowing all moisture to evaporate. If the floor is installed over radiant heat, first wait 48 hours; then turn on the heat to speed up drying. This scenario allows your drying time to be reduced to one week. Remember that terracotta tiles are extremely porous and small air pockets in the clay media can interfere with the transportation of moisture to the surface. Terracotta tiles can look dry on the surface in a short period of time, but will still be saturated with water inside. Always allow ample, properly prescribed time for drying.

When you are certain the reclaimed terracotta floor is thoroughly dry, use a high viscosity, naturally hardening sealing and priming oil. When applied, the sealing and priming oil will penetrate both the tile and the grout. It will fill any air pockets and form a sealed layer in the upper part of the terracotta tile. In 24 hours time, the sealing and priming oil will harden into a waterproof layer, forming an amber like material. This will lock in salts and minerals. Apply the oil liberally so that the terracotta tile soaks up as much oil as possible. After half an hour, check the floor surface and remove excess oil with the cloth. You may repeat this process if you feel it’s necessary but most floors only need a single application. The application of sealing and priming oil may initially exaggerate the color of the title but after a few days of drying, the resulting appearance will be that of the original tile installation with a slightly richer hue. After the one or two days of drying time, apply a surface finish. One good choice is Carnauba wax emulsion. It adheres to the sealed terracotta tiles and dries to a beautiful, hard matte finish. Your terracotta flooring will have a rich leathery luster without an overtly glossy appearance. For reclaimed terracotta tiles in bathrooms or other areas with lots of moisture exposure, use a durable semi-gloss acrylic finish. Where antique, reclaimed terracotta tile is installed in a shower, an even more durable epoxy sealer is the right choice.