The 5th floor of The Robertson Building, also known as 215 Spadina, sports a 4,000 sf extensive greenroof, which is enjoyed by the 40 tenants and visitors to the Robertson Building. Visitors emerge from an enclosed 400 sf glass atrium onto the wood deck viewing platform, which offers great views of the cityscape. The Robertson Building also has an interior green wall (Nedlaw living wall, with design by Beth Anne Currie) in the main lobby at 8m wide x 3.6m high (24 m? or about 258 sf) – the Biowall’s soil-less system recycles the nutrient rich irrigation continuously and has two one thousand watt light system grow lights that provide some seasonal UV light, which are on about four hours/day. Several varieties of native and exotic indoor flowering plants are set in pockets of a special fabric.
Designed and installed by Gardens in the Sky in 2004, half of the roof is vegetated and this is Toronto’s earliest urban example of a meadowlike roof, left to naturalize. Planted with over 10 species of Ontario native perennials, including Green-Headed Coneflowers, New England Asters, Goldenrod, and Black-Eyed Susans, the 6″ deep growing medium is highly organic at about 40%, which actually has the same proportions as when initially installed. Left to their own measures the plants have really flourished.At the time, no previous greenroof had been designed specifically with biodiversity as its motivating factor, and as a result, the roof has become a “poster greenroof” for the City of Toronto and its greening efforts. Aside from biodiversity of plants, the living roof also has a variety of other animals including bees, butterflies, and birds. Energy retrofits of the Robertson Building include a solar thermal system, and the tenants are so happy with the many environmental features of the building that there is a waiting list for new ones.