Onex Corp., one of Canada's biggest private equity firms, will invest $675 million and acquire a 39% stake in Jeld-Wen Holding Inc., the Oregon-based window and door manufacturer, Onex announced Wednesday.

Onex will put down $475 million for convertible preferred stock representing a 39% ownership stake in Jeld-Wen and pay another $200 million for a convertible note that can be redeemed within 18 months through proceeds from Jeld-Wen's sale of non-core assets, Onex said. The transaction is expected to be completed by June 30. Jeld-Wen will remain a private company and the firm's 20,000 employees will keep their stock ownership plan.

Jeld-Wen generated more than $3 billion in revenue in 2010, Onex said. It operates 123 manufacturing and distribution centers and has operations in more than 25 countries around the world. Its majority owner is the Trust of Richard Wendt, members of the Wendt family, and Jeld-Wen employees.

"We believe that Jeld-Wen's competitive position and well-known brands in markets around the world position the company very well to take advantage of the eventual recovery in global housing markets," Anthony Munk, an Onex managing director said in a statement. "We are delighted to be investing alongside the Wendt family, and look forward to working closely with Jeld-Wen''s management team and employees to build on the company's success."

Said Rod Wendt, Jeld-Wen's chief executive officer: "This is an exciting time in our company’s history and we’re pleased to be partnering with Onex, who shares our vision for the company’s future."

The moves come 13 months after Robert Turner became chairman of Jeld-Wen's board and nine months after the man Turner succeeded, Jeld-Wen cofounder Richard Wendt, died at the age of 79.

Onex calls itself "one of North America’s oldest and most successful investment firms committed to acquiring and building high-quality businesses in partnership with talented management teams." It manages roughly $14 billion, of which $10 billion comes from third parties.