The EY Tower is a skyscraper in Toronto, Ontario, Canada at 100 Adelaide Street West. The building was designed by Kohn Pedersen Fox and WZMH Architects. At its 1928 opening, 100 Adelaide Street West, was the Concourse Building which was a 14-story Art Deco structure. The building tenant was the Toronto Industrial Commission, which promot…The EY Tower is a skyscraper in Toronto, Ontario, Canada at 100 Adelaide Street West. The building was designed by Kohn Pedersen Fox and WZMH Architects. At its 1928 opening, 100 Adelaide Street West, was the Concourse Building which was a 14-story Art Deco structure. The building tenant was the Toronto Industrial Commission, which promoted the city as a hub of finance and business in Ontario. The building was famous for its mosaics by Group of Seven member J.E.H. MacDonald. The Concourse was designed by the firm of Baldwin and Greene. Oxford Properties took control of the building in 1998 and released plans to replace the Concourse Building with a new tower. The Concourse's defenders tried to find a buyer for the building, though Oxford refused to sell the site.