Imperial Oil Building, Modern skyscraper on St. Clair Avenue West, Toronto, Canada

The Imperial Oil Building is a 21-storey tower at 111 St. Clair Avenue West in Toronto. Its exterior is light grey concrete, partly smooth and partly vertically grooved, with small staggered windows on the narrow end and closely spaced vertical window columns on the long facade. It was converted into condominiums in 2010 and now has retail space on the ground floor.

The building was completed in 1957 and had originally been proposed as Toronto's new city hall before the plans changed and it became the headquarters of Imperial Oil Company. When the company eventually moved out, the tower was converted for residential use.

The lobby on the ground floor features two large murals by Canadian artist R. York Wilson, tracing the story of oil from prehistoric times to modern industry. Anyone passing through the entrance can see them without any special access.

The building sits on St. Clair Avenue West, a well-connected street with public transit stops nearby and comfortable sidewalks for walking. The ground floor is accessible from the street, so the lobby murals can be seen without going further into the building.

When it was finished, the building was the largest in the world with a fully welded steel frame, meaning no rivets were used during construction at all. This was so unusual at the time that it drew attention from engineers and builders across the industry.