Very often I observe detached or broken tiles in exterior installations. The most common areas are façades and residential driveways. But why does this happen? Our Caribbean climate presents challenges that must be taken into account when installing tiles outdoors.
In Puerto Rico, we experience sudden temperature changes caused by periods of intense sun followed by sporadic rain. These shifts—up to 15°F—affect the surface where tiles are installed. Concrete expands when temperatures rise and contracts when they drop. With this constant expansion and contraction within the substrate, how can we ensure the installed tile won’t break or come loose?
The key lies in selecting the right product and using the correct installation technique. Here are my recommendations for a successful and long-lasting outdoor tile installation:
- Whenever possible, use high-quality porcelain tiles thicker than 10 mm. These tiles are more resistant to traffic on floors and garage ramps. Avoid using cheap ceramic tiles under 7 mm thick, as they break easily.
- Avoid using natural stones that are sensitive to moisture, like slate. These stones expand and contract frequently, making them more likely to detach.
- Choose a polymer-modified adhesive with high flexibility. While many polymer adhesives exist, not all perform equally. Polymer adhesives are essential for bonding low-water-absorption tiles and substrates—something standard adhesives can’t handle. However, basic or budget adhesives that only meet ANSI A118.4 offer a rigid bond. For exterior installations, go with a flexible adhesive that also meets ANSI A118.11 standards. These are deformable and better suited for handling concrete expansion and contraction. For these cases, I recommend W2000 MAXX™ by Weco®, a highly flexible adhesive with Tri-Polymer Technology that offers the best durability for outdoor use.
- Apply the adhesive with ridges in a single direction (horizontal for façades), and press the tile using a slight motion perpendicular to the ridges to close them and achieve at least 95% coverage. For optimal coverage, apply a layer of adhesive to the back of the tile—a technique known as “back-buttering” or double-bonding.
- Follow the Tile Council of North America (TCNA) guidelines and leave movement joints at all corners and every 10 to 12 feet. This allows the tile to expand and contract with the substrate without lifting or cracking due to lack of space.
If your renovation project includes installing outdoor tiles—on walls or floors—make sure your contractor uses the right tile and adhesive for outdoor conditions and follows these best practices.
You can find W2000 MAXX™ Professional Adhesive and other products from the Weco® Professional System at The Home Depot, International Rustic Tile, Ceramica Alba, The Tile Shop, The Marble Shop, Stone & Tile, Cerapisos, Centro de Losetas y Baños, Centro de Terrazos y Azulejos (CTA), or ask for it at your local tile store or hardware shop. For more information, visit www.wecopr.com, facebook.com/wecopr, or call (787) 739-3751.
Engineer Carly Carrión is a remodeling specialist, founding partner of Black & White Diversified, One-Studio, and a contributor for Weco. For more ideas and useful remodeling advice, visit www.preguntaleacarly.com, facebook.com/remodelacionescarly, or call (787) 234-3777.