Aesthetic and Economical Benefits of Exterior Cladding Systems
According to many tile manufacturers, the ventilated facade system offers many benefits, including savings on construction and heating and cooling costs. Available in various tile sizes and colors, these systems still present architects with choices, and therefore, don't compromise designs. Additionally, with porcelain tile being lighter than most stone panels, there is less of a load on walls.
The ventilated wall system relies on a structural wall, an aluminum frame with vertical tubular studs secured to the structural wall by means of brackets. These brackets are designed with shape and dimensions to allow two direction adjustments -- inward and outward, and upward and downward - to compensate for possible structural wall irregularities.
Typically, there are two standard systems. While both offer the same structural support, the clip system -- where fasteners are attached to the front of the tile -- is not always favored for its aesthetic value. The other system is equipped with concealed brackets. In addition to appearance, cost is another consideration when choosing a system. The system with visible brackets can be about 15 to 20 percent less expensive than the one with concealed brackets.
The tiles were secured with the Mecanotubo-Tau system. Two aluminum profiles were inserted into the rear surface of the tile by two horizontal grooves that run the entire width of the tile. This system proves beneficial because it provides a large supporting surface, according to Tau. The anchorings of this system are bonded to the tile with high-performance elastomers.
In the Hidden Fixing System, also available from Alcalagres, 10-cm-long parallel vertical plates with slits are placed on the backside of the porcelain tiles in order to create a mechanic system. Stainless steel AISI 304 pieces are then introduced in these slits and screwed to the aluminum section. These are also anchored to the horizontal sections with force-fitted steel clips.
"Both systems are customized to the blueprints of each building," said Guillermo Puente, managing director of Alcalagres America in Miami, FL, adding that insulation is optional with each system. "It can be adjusted according to how much is wanted or needed."
A main feature of the ventilated facade system is the creation of a moving air chamber, which allows air to flow between the original facade and the sections covered with the porcelain tile. The amount of space between the tile and original facade can be determined during the project according to insulation or service needs.
The air jacket that is created between the structural wall and exterior veneer usually measures between 2 to 2 1/2 inches thick. This serves as the container for the insulating mat. By applying the insulating mat to the exterior surface of the structural wall, the maximum efficiency is obtained because all thermal bridges are cut, and dispersion of internal temperature is avoided.
In warmer months, a great amount of radiant heat is reflected away from the building. The heat that penetrates the chamber causes the stack effect, so that the building absorbs a small portion of the heat. In winter, load-bearing walls accumulate inside heat, while the insulating layer acts as a barrier to heat transmission to the exterior, causing heat to return to the building interior.
To increase the system's efficiency, an installation with open joints is recommended. It is said to better preserve the insulated material by letting air circulate slowly inside the air chamber and possible humidity is evaporated over time.
The tile facade systems also make it easier to change a tile if necessary, according to Puente. "The tile can be removed or replaced if there is a problem," he said. "With mortar, you have to breakdown the tile."
Another benefit of the exterior tile facade system is its ease of maintenance, according to Josep Domingot, general manager of Porcelanosa's operation in Anaheim, CA. Dust and other air pollutants don't adhere to the tile, making it easier to stay clean. Additionally, the company's Stone-Ker facades are non-flammable, are not conductors of electricity and have virtually no water absorption. And with an air chamber created with characteristics halfway between the outside atmosphere and the building interior, a substantial energy savings in buildings can be made. "The system can save up to 20 to 50 percent on heat," said Domingot.
Marketing in the U.S.According to Arturo Mastelli of AM&A Marketing Inc. in Key Biscayne, FL, the use of porcelain tile in ventilated facade systems has been increasingly growing in Northern and Central Europe for the past 30 years. Mastelli, who has years of experience working in the ceramic tile industry, has spent the last several years researching and lecturing about the use of these systems in the U.S.
"When I was in a business for the ceramic and porcelain tile, Imola Marketing & Services, an American subsidiary for Cooperativa Ceramica d'Imola, Italy, I always handled applications of exterior cladding and ventilated wall systems," he said. "I had a chance to build one actual building where I applied the system. I sort of became a specialist."
Mastelli's experiences led him to start his consulting company in the U.S. "I've had to re-write specifications, and have all these systems tested to conform and apply to local codes and requirements [in U.S. cities]. Due to these specific experiences, I put together enough information to share experiences with as many architects as I can."
The research, which was conducted in Miami, lasted several years, said Mastelli. He explained that in cities such as Miami, which is prone to forceful hurricane conditions, the building codes and requirements for exterior cladding systems had to be approved for wind resistance as well.
Environmental issues play a large part of the education Mastelli is passing on to architects in his seminars. "I had the chance to do additional research with the EPA [Environmental Protection Agency], and I have data showing and proving that buildings built according to regulations are much more efficient and more profitable," said Mastelli. "These buildings performed way over any other building that doesn't have compliance with Energy Star. The cost of energy to cool and heat a building is a good 48 to 51 percent of the total. When they realize there's a 25 percent savings on energy - it's a big chunk."
Using exterior facade systems also offers cost-effective benefits. "The economic aspect is something new and unexpected, but something important," said Mastelli.
Award-winning projectWhen budget came into play for the design of the Clearwater Center, the corporate headquarters of Sahara Construction in Bountiful, UT, a porcelain tile exterior facade system was a successful solution. The custom-designed cladding and installation system, which featured Italian tile manufactured by Mirage Granito Ceramico and supplied through DalTile of Dallas, TX, provided a lightweight, durable yet cost-effective and attractive facade. More than 14,000 square feet of tile was used for the exterior of the office building, which received the 2004 award from the Ceramic Tiles of Italy Design Competition in the commercial category.
"We wanted a Class A quality office building for a general contractor that can house other tenants in lease spaces until needed," said Project Architect David Brems of Gillies Stransky Brems Smith PC in Salt Lake City, UT. "We considered a number of skin products which would be found on high-quality Class A office buildings such as polished stone, metal, masonry, light and heavy precast concrete and ceramic tile. Ceramic tile was chosen because of its beauty, durability and cost."
According to Brems, this was the first time that he had worked with ceramic tile for an exterior facade system, and he was pleased with the results. "We wanted to panelize the exterior wall to control quality and speed erection time," said the architect. "We typically panelize polished stone and thought we could do the same with ceramic tile."
The most challenging aspect of the project was discovering what ceramic tile was available for use and could be delivered in time from the manufacturer, said Brems. But after everything turned out smoothly in the end, the architect said that he would use the system again. "The skin is durable, beautiful and lightweight," he said.
The design-build exterior cladding subcontractor for Sahara's new headquarters building was KEPCO+ of Salt Lake City. The company was the one who suggested using porcelain tile on the patented prefabricated Cygnus panel system. The aesthetic appeal of the building is enhanced by the layout of the Italian tile in two different finishes and sizes. The natural-finished tile was employed for the majority of the building, while the polished tile was used for the entrance and "pop-outs" on each side of the building as well as an accent to breakup the predominant natural tile on the structure.
"The uniqueness about this system is that it allows for the use of a thinner material, making it very lightweight and extremely flexible, which is a real plus in seismic areas, said Bruce Knaphus of KEPCO+. "This was a budget-oriented project, and it had a tight schedule. We needed to find something cost-effective, durable and attractive, but that could meet a very demanding construction schedule. The tile manufacturer was able to produce and ship the tile in seven weeks from Italy, which was important, for adherence to the schedule."
Two varying tile sizes - 24-by-24 and 12-by-24 inches -- were used for this project. For the majority of the building, 24-by-24-inch pieces of Mirage's DG03 Ungartetti natural were employed. Stripes were created on the building with 12- by-24- and 24-by-24-inch pieces of DG03 Ungartetti polished.
In total, 50 prefabricated panels were used to clad the exterior of the Clearwater Center. "It took about five weeks to apply the tile to the panels in our shop," said Knaphus. "The panels spanned a full bay. We shipped the panels to the jobsite and erected them in one day."
According to Knaphus, KEPCO+ has used the Cygnus panel system for various jobs prior to this project. "We have used it for both stone and tile, but we have used it for quite a bit of ceramic tile," he said. Knaphus explained that Sahara Construction has been a client of KEPCO+ for a long time. Being in the building industry itself, the company was familiar with the Cygnus panel system. "When we suggested this [system] to Chelsey Smiley, one of the company's vice presidents, this was something of interest to him, and he felt secure with it. He had had some exposure to the panel system when working in Los Angeles in the 1980s."
The Cygnus panel system has been patented since 1982. "I've been a licensee since 1984," said Knaphus. "There are only six to eight licensees in the U.S."
Other projects where KEPCO+ has used the Cygnus panel system for porcelain tile include the four building NCR E&M complex in San Diego, CA, and the B.A.C. Plaza in Stockton, CA. Additionally, other contractors have used the system on such large projects as the Naval Intelligence Center in Washington, DC, where 250,000 square feet of tile was used, the Mayo Clinic in Florida, and the IBM Branch Office in San Diego, CA, according to Knaphus.