Integral House has sold to a mystery buyer

Integral House has sold to a mystery buyer

After two price drops and untold thousands of dollars spent on advertising, Integral House, the former home of James Stewart, the late mathematician and textbook magnate, has finally found a buyer. The sale was announced this morning by Trilogy Agents, who spent almost a year and a half marketing the property to a vanishingly small group of wealthy buyers with both the money and the inclination to buy a home that was made to measure for just one person.

Stewart, who earned his fortune writing a series of calculus textbooks used in classrooms around the world, bought a home on Rosedale’s Roxborough Drive in 2002 for $5.4 million, then demolished it and commissioned Toronto’s Shim-Sutcliffe Architects to build a completely new mansion on the land, customized to his specifications. Integral House has curves like no other building in Toronto, and it shows an obsessive attention to detail: there’s a two-storey living room with limestone floors that doubles as a concert hall for 200 people, an office with a panoramic view of the ravine in the backyard, and a master bedroom accessible through a staircase lined in art glass. Even the doorknobs are custom-made—cast to resemble the mathematical integral symbol common in Stewart’s equations.

The house is magnificent, but it’s essentially a bachelor pad: in 18,000 square feet there are only four bedrooms, and two of them are off in a separate guest suite with its own kitchen and bathroom. When Stewart died in 2014, the inheritors of his estate put the house on the market for $28 million the following year. It was clear that finding a buyer was going to be difficult. Over the next few months, the asking price dropped by almost $10 million: first to $22.9 million and then, in August, to $19.5 million.

Paul Maranger, of Trilogy Agents, was the property’s lead listing agent. As with many houses in this price range, he says a complex sale strategy was needed. “We advertised in Bombardier Experience magazine, which targets private jet owners,” he said. “We advertised in En Route magazine to reach high-level corporate businesspeople who would fly Air Canada. We advertised in Mercedes magazine.”

Maranger isn’t disclosing the identities of the buyers. He’ll say only that they’re a family with “strong Toronto roots” and “multiple properties around the world.” He’s similarly secretive about the sale price. Stewart’s estate has said that at least some of the proceeds will be donated to his favourite charities, which include the University of Toronto, St. Michael’s Hospital and the Community One Foundation.

According to Maranger, the buyers aren’t planning any changes to the house’s concert hall, but they are looking forward to altering the layout of the bedroom level to better suit family life. So here’s a last look at Integral House’s interior in mint condition.

The concert hall:


Another view of the concert hall:


The dining area:


The kitchen:


The indoor pool, with a view of the ravine in the backyard:


The master bedroom is one of only four bedrooms in the house:


The view from the rear: