In Colorado, underground work is complete on IKEA’s Centenial store in the Denver-area. The store’s foundation and structure work can now begin. The system will use 130 holes, drilled 5.5 inches wide and 500 feet deep, for pipes to hold heat-transferring liquid circulating through underground loops. It will be used to both heat and cool the 415,000 square-foot store as conditions require. It will be the first U.S. IKEA store to integrate a geothermal system.