A New Look at Recycling

Is a post-consumer pound of recycled material better than a postindustrial pound of the same material? In both cases, the pound represents material diverted from our growing national waste stream, at least 10 percent of which is from construction materials and demolition debris, according to the EPA. One can argue that the post-consumer pound is harder to get—or that it represents a valuable change of thinking. Though this is true, it’s also true that many industrial processes are rewarded for wastefulness, when recovery and closed-loop processes cost more than transport to landfills or simply dumping waste and process water. That’s why developers of the International Green Construction Code (IGCC) in 2011 held hearings to challenge the notion that types of recycled content should be favored in the code as they have been in the U.S. Green Building Council’s LEED program. “Reducing the benefit of diverting industrial waste could in fact discourage manufacturers from continuing their waste diversion efforts,” according to the Trade Commission of Spain, Coral Gables, Florida, which represents Tile of Spain. Following this line of thinking, the IGCC’s public version 2.0 called for a goal of at least 55 percent of a project’s materials to be of any recycled origin. In IGCC’s Section 503 – Material Selection under section 503.2, the code called for that 55% to come from used materials, recyclable materials, biobased materials, and local or “indigenous” materials, as well as “at least 25 percent combined post-consumer and pre-consumer recovered material” that must also be recyclable. IGCC says “any combination” will do—an important advance for green building and the environment.

Specific opportunities for evaluating the potential use of ceramic tile can be found in the various LEED categories:

Indoor Environmental Quality
Inert Is In

In early versions of LEED, credit opportunities reflected the makeup of the constituencies involved in creating the certification system. Carpet manufacturers, actively involved in the program, worked to reward building projects that employed carpets with low VOC content. The credit originally known as Low Emitting Materials – Carpet Systems, was eventually revised to cover all types of flooring,

The credit Credit 4.3 Low-Emitting Materials—Flooring Systems addresses IEQ by offering three compliance paths: First, by meeting green label programs such as FloorScore or VOC limits set in IEQ credit 4.1; second, by meeting the California Department of Health Services' test protocol for VOCs; or third, not exceed LEED-listed maximum emissions levels based on determinations using the ICC Evaluation Service guideline. In this latter option, tile-setting adhesives and grout must not exceed VOC limits in LEED addressing adhesives and sealants.

For this reason, green specs for ceramic and porcelain tile must carefully adhere to IEQ credit 4.1, Low Emitting Materials – Sealants and Adhesives. Ceramic tile adhesives must have a VOC limit of 65 grams per liter (g/L), less water. This applies to all adhesives and sealants for ceramic tile assemblies used on the interior of the building – in other words, “inside of the weatherproofing system and applied on site.” The level of VOC content reflects California's South Coast Air Quality Management District (SCAQMD) Rule #1168, which for years has been the most advanced criterion for VOC content and emissions.

In spite of these strict rules, many green building practitioners ask why we use products with any VOCs at all if they can be avoided entirely? As Charlottesville, Virginia-based environmental advisor and architect William McDonough has frequently admonished, “less bad” isn't better. “While emerging 'green' codes have created considerable improvements in the environmental performance of new buildings, they are still the product of a consensus-based exercise largely focused on trying to be 'less bad,'” he wrote in Perspecta in 2004. They are trying to “minimize the impact of the old industrial system by making it more efficient. This yields both low standards and flawed designs.”

Today's more advanced thinking includes adherence to the “Precautionary Principle,” established in the 1992 Rio Conference, in which designers avoid “substances that are known or suspected to be associated with an adverse finding in relation to human and environmental health.” In the European Union, this principle—which requires the party taking an action suspected of causing harm to the public or environment—bear the burden of proof for proving it is safe.

The architecture firm Perkins+Will, for example, released in August of this year a report listing 374 known asthmagens in the built environment as part of its “Transparency Project,” which calls for more information on constituent material so that firms can more easily create healthier buildings. “It's a largely opaque market,” Peter Syrett, a senior designer for Perkins+Will who led the report's development, recently told Forbes. We don't know “what a product is made of unless the manufacturer tells you, and only a handful of them do,” he added.

Fortunately, an addendum to the LEED IEQ credit 4.3 added in April 2010 qualified ceramic tile for an exemption from the VOC testing requirement, along with other “mineral-based finish flooring products.” Using ceramic tile, architects can apply for this credit without third-party certification.

Materials & Resources
Reduce and Reuse

These credit areas reward the diverting of waste from one-way trips to landfills. The Materials & Resources (MR) credits are given for recycled content, including all post-consumer and 50 percent of pre-consumer material that would otherwise add to landfills. Other credit categories are for rapidly renewable materials and the reuse of construction materials.

Ceramic tile holds high potential for salvage or reuse, as outlined in MR Credit 1.2: Building Reuse – Maintain Interior Nonstructural Elements. Yet ceramic tile can also be preserved in situ, contributing further to MR Credit 1.1: Building Reuse—Maintain Existing Walls, Floors and Roof. For MR 1.1, reusing 55 percent of the total earns one point; a 75 percent reuse gets 2 points; for 95 percent it is 3 points. (If the project includes an addition more than twice the floor area of the existing building, however, the credit may not apply.)

The intent of both credits goes beyond reducing waste and the global impacts of using new building materials. According to the USGBC, they also “extend the life cycle of existing building stock, retain cultural resources,” and even reduce associated transport impacts. The resilience and integrity of structural floors and exterior walls with ceramic tile finishes or cladding tends to make them good candidates for reuse, according to Atlanta-based green building consultant Carl Seville. Options include refinishing in place, refurbishment and grinding the tiles for use as gravel.

“Because quality ceramic tile is extremely durable, it outlasts most other types of flooring,” says Tile of Spain's Fasan. “This enables the salvage of even antique and historic installations.” Fasan adds that the potential reuse of a ceramic tile floor system, rather than premature replacement, can slash the costs and scope of renovations initiated by flood or fire insurance claims. “Ceramic tile is one of the only materials which can survive these disasters,” she says, enhancing its functional resilience. Wood, carpet, linoleum, rubber and other common flooring types may need complete removal after water or smoke damage.

Ceramic tile performance in these situations, on the other hand, is good news for MR 1.2, which encourages the use of existing interior nonstructural elements—including walls, doors, floor coverings, and ceiling systems—in at least 50 percent (by area) of the completed building, including additions, as calculated by area. Here again, projects with large additions won't qualify for the credit, and any building elements that are inefficient in terms of energy and water consumption or that pose a contamination risk to building occupants should be removed.

For MR 3, which rewards other kinds of reuse, ceramic tile can play a role as an inert, safe and clean fill material that has been used for hundreds of years as road base, backfill, aggregate and as added material for the regrading of sites. Other types of flooring may also be suitable as fill, though not carpet, linoleum or wood plank.

These credits are also ideal opportunities to take advantage of tile-over-tile applications with thin porcelain floor tiles over original ceramic tile surfaces. Other flooring systems may allow for similar overlayment; the key is a stable, smooth and compatible substrate to accept the new adhesives, backing and material layer.

In addition, the overcladding of building exteriors with rainscreen systems has led to more ventilated porcelain-tile façade systems retrofitted over original exteriors, including masonry and glass-and-steel enclosures.

Ceramics manufacturers are constantly pushing boundaries of design possibility. Exploring volumes by bending tiles for performance cladding is just one example. Photo courtesy of Tile of Spain / Apavisa