Itself an Art Moderne masterpiece, the Eaton's Seventh Floor was at the heart of Toronto's cultural life for many years. The Auditorium played host to the major performers of its day, including Billie Holiday, Duke Ellington and Frank Sinatra. The first performance of the National Ballet of Canada was on the stage of the Eaton Auditorium. Canada's own Glenn Gould, fond of the Auditorium's excellent acoustics, used the hall for a number of his recordings.
The Round Room was, as the name suggests, a circular room, with circular mouldings in the domed ceiling and recessed alcoves in the corners. At the centre of the room stood a Lalique fountain, lit from below. Carlu was responsible for all aspects of the dining room's design, from the lighting fixtures to the Royal Worcester china, the stemware, and the waitresses' black uniforms. Carlu's wife, Natasha, designed the murals on the walls, depicting various scenes of pastoral life. For years, the Round Room was one of the most elegant places to dine in Toronto.
Although the new owners had originally agreed to preserve the Seventh Floor, they eventually determined that its preservation and restoration was not financially feasible, and they applied for a demolition permit to convert the entire floor to office space. After a lengthy court battle with the City of Toronto, the Ontario Court of Appeal ruled in 1986 that the 1975 designation of the building under the Ontario Heritage Act protected the Seventh Floor from demolition. Despite several changes in building ownership, and the efforts of local heritage advocates, the Seventh Floor was sealed off for many years and allowed to deteriorate; although it was protected by law, there was no legal obligation to use or restore it.