Architectural Record BE - Building Enclosure

Ceramic Tile: Solutions for Holistic Sustainability

[ Page 5 of 8 ]           
Sponsored by Tile of Spain
C.C. Sullivan
This test is no longer available for credit

Tile Adapts to Evolving Needs

Applications of ceramic tile go beyond this kind of visual and formal innovation. In fact, they present a framework for achieving an evolving definition of sustainability.

EPDs available for European and North American tile sources, for example, can contribute to earning up to two points under LEED v4 provisions, which require the use of at least 20 products with EPDs and 50 percent of products with improved life-cycle performance. Additionally, ceramic tile can in some cases “contribute toward earning up to 30 points under Green Globes provisions for core, shell, and interior fitouts,” according to TCNA. For the Collaborative for High-Performance Schools (CHPS) ratings, use of ceramic tile can help add three available points for using at least 10 products with EPDs.

A recent TCNA report on the EPD developed for major North American manufacturers explained that the data was aggregated among a dozen or so manufacturers, representing more than 95 percent of the tile produced in Canada, Mexico and the United States. Cerame-Unie, a European ceramics industry association, has also unveiled a number of initiatives, including its role beginning in 2013 as a founding member of ECO Platform, which has initiated a Europe-wide accepted EPD established between EPD program operators, European trade associations, green building councils, and certification bodies as well as LCA practitioners. This not only helps the tile industry by allowing multiple manufacturers to share the often-heady costs of undertaking an EPD, but it also paves the way for architects and specifiers, who can count on a large pool of tile producers with EPD documentation, to reduce the effort required for the construction industry to develop EPDs.

Manufacturing practices have also evolved over time to boost materials savings and efficiencies in the production of ceramic tile. As experts note, LCAs and EPDs already reflect the fact that tile is manufactured from several perpetual resources, including clays and feldspars, which are viewed as effectively unlimited. “In this way, tile manufacture does not qualify for the LCA impact of mineral depletion,” says Tile of Spain’s Fasan. “These base materials are like salt, gypsum, and solar energy, which are considered inexhaustible for practical purposes or with reserves estimated to last at least 700 years based on relevant ASTM standard definitions.”

Other impacts considered for LCA and EPD documentation include several factors that directly impact human health. Among them are:

  • Embodied energy for the given product, which is the process energy required for mining, manufacturing, transport, installation and the like;
  • Waste
  • Global warming potential (GWP), which is how much heat a given greenhouse gas traps in the atmosphere;
  • Carbon footprint, the total greenhouse gas emissions attributable to the product;
  • Smog, also called ground-level ozone;
  • Acidification potential, describing an increase in acid level (or decreased pH) in soils and waters caused by such pollutants as sulphur dioxide and nitrogen oxide, which can come from some power plants; and
  • Eutrophication.

To reduce the influence of several of these types of impacts, leaders in the global ceramic tile industry have developed closed-loop production and waste management methods seen as exemplary among varied industries. These tend to allow cleaner processes for manufacturing as compared to previous methods, especially in terms of particulate reduction, emissions control, and carbon footprint.

On the energy side, novel process enhancements include closed-loop heat recovery, sometimes called heat siphoning, to capture thermal energy from the energy-intensive firing stage. Most ceramics manufacturers employ roller kilns fueled by natural gas, and in the past more than 50 percent of the energy input would be lost with flue gases and through cooling gas exhaust stacks, according to engineer Ana Mezquita, with the Instituto de Tecnología Cerámica, based in Spain. Many tile producers also recover heat in the atomizer, which spins the wet tile materials, or slurry, in a chamber with hot, moving air to create a powder that can be formed into ceramic materials.

Today, depending on kiln operations, cooling gases are recovered in the firing chamber, and waste heat from kiln exhaust can be captured for use in cogeneration. The cogeneration systems, also called combined heat and power or CHP, help close the energy loop by using previously wasted heat output as input energy. About 250 CHP plants are currently in use in Europe, according to Renaud Batier, director general of Cerame-Unie, representing a total installed capacity of about 700MW.

Another environmental benefit of modern tile production methods has been the use of improved raw materials, which reduce processing needs while also including more recycled content in the batch formulations.

Holistic and Integrated Specification

As manufacturers become more efficient, they also become more profitable. So why should these improvements matter to architects and specifiers? First, “there’s a lot of resistance to changing the way things are done,” according to Dr. Diana Fisler, environmental construction platform leader for a major insulation manufacturer, speaking at a recent EcoBuilding Pulse roundtable. “As we want to move to more sustainable products, the construction industry is very price-driven, so how do we get value from that? If we have a one-to-one product or a more expensive sustainable product,” she asked, will architects and contractors value those as highly?

For architects, the first advantage is knowing that the same or equivalent product is actually greener than it was a decade ago—a significant fact for traditional material categories such as ceramic tile. As a result, product costs rise more slowly as the societal and environmental costs of water and energy use go down. “That means top-of-line products become more cost-effective for the specifier,” says Rocamador Rubio Gomez, director of the Trade Commission of Spain, Miami. “While keeping cost of goods low is important on micro-economic scale for manufacturers, we also see the regional and global benefits of water recapture and reduced fossil fuel consumption on a macro-economic scale. This also helps organizations, municipalities and federal agencies meet their carbon reduction goals and air quality targets.”

Today, ceramic and porcelain tile are manufactured with less energy and increased water recapture as compared to 10 years ago. That makes equivalent products, such as these tile planks with a look of reclaimed wood, more cost-effective for the end-user.

Photo courtesy Tile of Spain

Today, ceramic and porcelain tile are manufactured with less energy and increased water recapture as compared to 10 years ago. That makes equivalent products, such as these tile planks with a look of reclaimed wood, more cost-effective for the end-user.

 

[ Page 5 of 8 ]           
Originally published in Architectural Record

Notice

Academies