Integral House’s mystery buyer is one of the most powerful men in Canadian finance

Integral House’s mystery buyer is one of the most powerful men in Canadian finance

Integral House, viewed from behind

Last month’s news that Integral House had finally found a purchaser left plenty of questions unanswered. Mainly: who was the buyer? The famed mansion, custom-designed by Shim-Sutcliffe Architects, had languished on the market for a year and half, and no wonder: it’s an ultra-modern, 18,000-square-foot Rosedale home with just four bedrooms (two of them hidden away in a separate guest suite) and, instead of a living room, a giant, two-storey performance space designed to hold 200 guests. Only a very wealthy person with an extremely busy social calendar could possibly justify the expense.

The house’s listing agent, Paul Maranger of Trilogy Agents, would say only that the purchasers were a couple with two children, “strong Toronto roots,” and “multiple properties all around the world.” Maranger later told the Globe that the pair were “high-profile” and musical. Were Elton John and his husband about to move to Rosedale?


In fact, Integral House’s mystery buyers are in finance. They are Mark Machin, the new CEO of the Canada Pension Plan Investment Board, and his wife, Melissa Mowbray-D’Arbela, an investor and strategy consultant. The couple have two children.

Machin, during an interview with AVCJ Televison. Image from YouTube

Machin is a U.K. native who started his financial career at Goldman Sachs. He spent nearly two decades rising through the ranks of the investment bank’s Asian operations. He left Goldman in 2012 to take a job as president of the CPPIB’s Asian arm, and in June was promoted to CEO after the previous CPPIB head, Mark Wiseman, announced his departure. Machin’s family moved to Toronto from Hong Kong so he could take the new job, where he’s responsible for investing Canada’s $280-billion nest egg.

According to land registry records, the price Machin and Mowbray-D’Arbela paid was $14,950,000—not including $590,000 in land transfer tax. It’s a hefty price, but it’s significantly less than Integral House’s sellers had initially hoped for. The house was first listed for sale in 2015, for $28 million. Over the next few months, the sellers lowered the asking price twice: first to $22.9 million and then, in August, to $19.5 million.

Integral House’s performance space.

Integral House was completed in 2009 for James Stewart, a math textbook author and music aficionado, who lived in the house until his death in 2014. The place has a daringly curvaceous floor plan, a spa, and a home office with a ravine view. The flooring in the performance space is creamy limestone, and the stairway to the bedroom level is lined in blue, hand-blown glass. Billionaire media magnate David Thomson has a house next door.

Stewart used the house as a venue for elaborate events, and it appears as though that tradition will continue.

“James Stewart created a remarkable building, a wonderful venue for culture, performance and other arts,” Machin said in an emailed statement. “Our family is thrilled to own this extraordinary house in Toronto. We intend to continue to honour his community-oriented legacy by making our home available for events in the future.”