The headquarters for PepsiCo's Frito-Lay Northern America, REI stores in Texas and Illinois and more than a million square feet of office space in Denver managed by Transwestern have achieved gold and silver LEED ratings.

All but the two REI stores, which opened last year, received their green building certifications as existing structures.

Frito-Lay's building in Plano, Texas, received a gold rating under the U.S. Green Building Council's standards for Leadership in Energy and Environmental Design for Existing Buildings.

"There are many challenges to retrofitting a 25-year-old building to meet LEED EB-Gold standards," George Guck, director of facilities and corporate services for Frito-Lay North America said in an announcement last week about the certification.

Elements that helped Frito-Lay headquarters receive its gold rating include a solar thermal water heating system, which warms all the water used in building; new high efficiency chillers that reduce annual energy use by 975,000 KWH; and a water conservation program that includes landscaping with native and adaptive plants. The company also said it is the city of Plano's top recycler.

In Colorado, the Denver Financial Center, owned by affiliates of USAA Real Estate Company, and One & Two Greenwood, owned by Franklin Street Properties, received LEED-Gold certification.

The building at 1125 17th Street received LEED-Silver certification. That structure and one at 1999 Broadway, which was certified at LEED-Silver level in August, are owned by Transwestern Investment Company, Broadreach Capital Partners and Equity West Investment Partners.

Upgrades in the restrooms in all four buildings have saved 4.3 million gallons of water. Other efficiency upgrades resulted in avoiding 28.8 million pounds of carbon dioxide.

Transwestern's property management portfolio includes 7.3 million square feet of LEED-certified space in 29 commercial buildings. The firm is seeking certification under LEED for Existing Buildings: Operations & Maintenance for 120 projects at client properties.  

REI stores in Round Rock, Texas, and Lincoln Park, Ill., earned LEED-Gold certification for Commercial Interiors. The stores opened in September 2008 and October 2008, respectively.

The REI in Round Rock, designed in collaboration with Gensler, is the second to be built according to REI's sustainable design prototype. (The first was the REI in Boulder.) The Lincoln Park site was built along a more traditional design but nevertheless achieved LEED-Gold certification, the second highest rating in the four-tier system.

Atop the Round Rock store are a solar array, a cool white roof and Solatubes skylights. Inside, the flooring, rugs, countertops and some walls are made out of recycled material including tires, tennis shoes, scrap aluminum and sunflower seed husks. In addition to bike racks for all who come to the store to use, there are showers for the employees and a bike repair shop.

REI announced the certifications this week. Other green properties in the company's portfolio include REI Portland store, which LEED Gold for Commercial Interiors; REI Pittsburgh, LEED Silver for Commercial Interiors; REI Boulder, LEED Gold for Retail as well as Commercial Interiors; and the REI Bedford Distribution Center, LEED Silver for New Construction.

Image courtesy of REI.