New York City-based CTA Architects’ sustainable renovation and expansion of the Bronx Charter School for Excellence (also known as Bronx 1) has earned the high-performing school LEED Silver certification. In addition to renovating an existing 10,000-square-foot, two-story building, the architects added a new seven-story, 35,000-square-foot tower, a 4,500-square-foot, two-story annex and a 4,7850-square-foot, double-height gymnasium to better accommodate the charter school’s growing student enrollment.