Opened in the fall of 2005, one of the best things about this Dalhousie University building, besides its open airy five-storey atrium, is its attention to environmentally sound design. Kenneth Rowe has low-flush plumbing, recycled-material use, lighting occupancy censors, operable windows, thermal insulation and a water-source heat pump. Rick Mercer would be proud. Or he would be if we still had the One-Tonne Challenge. Or Kyoto. Dalhousie University, 6100 University

1st runner-up The Paramount, 1545 & 1551 South Park

2nd runner-up Martello Tower, Point Pleasant Park