Sustainable Flooring: Multiplicity - Sustainable Flooring

The new City Hall in Orinda, Calif., was intended to showcase the city’s commitment to civic buildings that strengthen the community fabric and protect the environment. When the pending LEED Gold status is awarded, this will be the first city hall in California to earn the Gold rating from the U.S. Green Building Council (USGBC). In going for the Gold, every building component in the 14,000-square-foot structure plays a role, including the floors. A combination of diverse flooring materials including concrete, ceramic tile, cork and linoleum contributes to this modest, two-story model of sustainable design.

The city of Orinda hired Siegel & Strain Architects of Emeryville, Calif., a firm with almost 15 years of green design to its credit, to design the new city hall. According to project principal Henry Siegel, FAIA, the city wanted an appealing civic presence, a design that helped foster a connection between citizens and city staff, and a space that met a high level of environmental responsibility. And while some aspects of the design are more contemporary than others, including wall signs that light up and inform occupants to open windows for natural ventilation at opportune times, other design elements make smart use of traditional materials — especially the flooring.

The green flooring products were chosen based on their ability to exhibit sensitivity to the environment in their manufacture, installation, daily use and eventual disposal. A good example is the concrete. Cement manufacturing is one of the largest global sources of CO2, and the 50 percent slag concrete mix used at Orinda greatly reduces those emissions. The linoleum, nature’s original resilient floor, is made from renewable raw materials including linseed oil, wood flour, cork flour, organic pigments and limestone on jute backing. The cork tile, in light and medium shades, is responsibly harvested from a species of oak found in the Mediterranean and Portugal. Only the outer bark, which grows back in a matter of years, is used in the flooring. The tree is not harmed, nor does it need to be cut down, and typically lives for 150 to 250 years. The ceramic floor tiles are certified by Scientific Certification Systems, and are manufactured with 55 percent recycled glass. The domestically made tiles are aesthetically pleasing, durable and have an easy-to-clean surface that resists stains and water. Other floor finishes and accessories used throughout the interior include carpet tile made from recycled fiber and backings, and natural rubber wall base.

Architects and designers originally set out to achieve a Silver LEED rating for Orinda City Hall, but when all the building’s sustainable features were reviewed against the USGBC’s Gold checklist, they realized the higher rating was a possibility. More importantly, no aesthetic compromises needed to be made for the sake of sustainability, flooring included.