Due to its uniform finish, lightweight and versatile nature, ceramic tile and stone have been used as exterior finishes and cladding for buildings around the world for decades and this trend shows no signs of slowing down.
Exterior facades can provide a unique visual impact in addition to thermal and acoustic insulation. Ceramic tile installations often contribute to green building certification, making them both visually appealing and architecturally functional — when executed properly. In order to completely benefit from the aesthetically versatile nature of these finish types, distinctive installation techniques are required.
Proper Design and Preparation Are Paramount
The proper performance of an exterior facade begins with the design team who is responsible for ensuring that all components of the entire wall assembly are suitable for the climate and conditions.
An exterior facade will face very harsh conditions -- ranging from weather, thermal exposure, thermal shock, building movement and potential seismic events, just to name a few. Along with selecting the appropriate finishes for these conditions, the installation materials, which can include leveling mortars, membranes, air barriers, adhesive mortars, grout and sealants, must also be able to withstand these conditions and be compatible with the finishes.
Weather protection on the jobsite and during the initial cure of the materials is a necessary practice when preparing for the installation. This may include providing tenting, enclosures or shading to protect the installation from direct sunlight and wind. Also, climate control (heating the enclosure) may be necessary to ensure the temperature of the substrate and the installation materials remain within the recommended guidelines of the installation materials manufacturer. The proper design, placement and composition of movement joints within the assembly is critical to the long-term performance of facades.
Work with an Experienced Team
The best way to select the appropriate installation system for the intended project is to involve the tile installation materials manufacturer early on in the process. When selecting an installation system, look for those that include a comprehensive systems warranty that is backed by years of successful installations. The installation should also be designed in accordance with well-proven installation methodology that is governed by industry standards (e.g. International Standards Organization [ISO] and American National Standards Institute [ANSI]).
For example, an installation specification should be written with ISO standards in mind that have higher performance standards for adhesives and would be better suited for ceramic installations. This specification also includes extended working time, sag resistance and flexibility characteristics. A product specification for an adhesive mortar for an exterior facade could potentially be C2TES1 or C2TES2, which features superior flexibility and performance. Alternatively, similar specifications could be written around ANSI standards with an ANSI A118.15TE designation for high performance, sag resistance and extended working times.
Since installing ceramic and stone tile to exterior facades is so different from installing tile on say a kitchen or bathroom floor, select a contractor based on their knowledge and ability to perform these installations with a proven successful history of installation. Unlike interior installations, there are other exterior veneer building elements that may be required to be incorporated into the assembly during the design process. These elements could include air and water barriers, continuous rigid insulation, drainage planes, vapor retarders, etc., which all play a vital role in protecting the structure from moisture and weather intrusion and staying energy efficient.
Careful Consideration of Products
The key to a successful end result relies on close selection and detailing of installation materials that adhere to the unique characteristics of each project. This is not a “one size fits all” case scenario – not all installation materials are appropriate for these demanding applications. As previously stated, weather oftentimes (if not always) plays a role during the installation of ceramic tile on exterior facades. The installation materials will always need to meet higher performance industry standards in order to deal with many of the environmental and on-site conditions of the project.
With that said, all of the installation materials must be weather and shock resistant, be complementary and compatible with each installation component, be easy-to-use and have all of the required performance properties to handle the application. The repercussions of a poorly structured facade system can not only affect how the exterior performs, but also the stability of the building -- potentially leading to millions of dollars in damage and extensive repairs that could have been avoided with proper materials and preparation. But when done correctly, ceramic tile and stone on exterior facades is an excellent choice that you won’t regret.
Proper care and expertise applied in these demanding applications can result in a breathtaking project completion that can be admired for years to come. This is why it is essential for the installer to work closely with their installation materials manufacturer for recommended guidelines.