Green Squared


In 2021, 3.11 billion square feet of ceramic tile was installed in the United States.21 While transparency in the tile industry is increasing, full disclosure of material content is rare, exposing consumers to ingredients with a variety of health concerns.9


The ANSI A138.1 Green Squared Standard is a voluntary standard for tile and tile installation.16 Launched by the Tile Council of North America (TCNA) in 2012, the Green Squared Standard is the only sustainability program in North America regulating environmental and health criteria for tiles and their installation.3


About the standard

Green Squared can apply to a variety of products made from ceramic and glass, as well as glazed tiles and tiling systems. The Green Squared FAQ page  lists all products within the scope, including liquid additives, liquid and paste installation methods like adhesives, and dry powder installation methods like mortars and grouts.


Green Squared is known for its multi-attribute approach that tackles product characteristics, manufacturing, end-of-life product guidance, corporate governance, and innovation to guarantee green criteria. 3

The Green Squared certification indicates that a product is third-party certified and meets all ANSI A138.1 requirements.2 The standard defines a unified and consistent interpretation of product sustainability.3


Cautions with tile content

There are a few cautions to look out for when working with tiles:


Lead oxide in glazes – Although ceramic tile is relatively sustainable, it has been associated with toxic chemicals like lead oxide. Although U.S. factories have phased out most toxic metals from ceramic glazes, some international suppliers remain unregulated. Lead, zinc, and barium content of U.S. ceramic tiles dropped by 93.6% between 2002-2012.9


Nanoscale particles in coatings – It is important to note that ceramic tiles can still contain nanoscale particles in surface coatings applied in a secondary process after glazing that have silver, copper, and titanium. These particles are less researched, but are linked to pulmonary system issues.9


Non-specified recycled content can pose a risk when it contains lead from cathode-ray tubes in old TV sets.


Installation products like epoxy grouts and sealers are known to carry PFAs.19, 11 The most studied of these substances is a chemical called PFOA, which is linked to kidney and testicular cancer, elevated cholesterol, decreased fertility, thyroid problems, and decreased immune response to vaccines in children.20 Ceramic adhesives may also contain antimicrobials and heavy metal contaminates in imported tiles which can be persistent, bioaccumulative, toxic, and contribute to bacterial resistance and endocrine disruption.12


Ceramic and porcelain tiles can carry toxic additives in their pigments and glazes.14 Try applying any of the following Green Squared considerations for tile:


  • Spec ANSI A138.1 Green Squared products through Green Square’s online library 13 that classifies materials by brand, EPDs, certifiers, and rating systems.
  • Prefer tiles made in the U.S over imported tiles that may not be subject to lead regulations. 14
  • Prefer tiles with publicly disclosed content material including grits, frits, and pigments. 9
  • Choose tiles with an abrasion rating of at least 4+ when working with undisclosed content.9
  • Prefer tiles with coatings that do not contain antimicrobials. 9
  • Avoid tiles with non-specific, post-consumer recycled content known as CRT tiles, made up of cathode ray tubes from old TV sets.14
  • Avoid epoxy grouts and sealers with PFAs marketed with “oil repellent” properties.11
  • Spec adhesives that don’t contain formaldehyde and meet the SQACMD VOC limits of 65 g/L. 17
  • Refer to this Tile Countertops 15 newsletter for information on specifying tile countertops.



Visit these sources for more information.


  3. standard addresses product characteristics%2C manufacturing%2C end of product life management%2C corporate governance%2C and innovation%2C and it establishes the spectrum of environmental and social criteria most important to today’s green building world.
  16. A138.1 is the industry standard for sustainable tile and tile installation products.
  19. are man-made chemicals that have been used in industry and consumer products worldwide since the 1940s.