Lagan, who sold his building material business for £455m to Breedon Group last year, aims to expand the operation in tandem with his existing FastHouse brand.
Founded in 2008, Frame-Tech manufactures and installs over 1,000 homes a year across the north of England, employing around 60 people.
Last year it reported revenue of £13m.
Lagan Investments, which bought the majority stake, is eyeing the UK timber frame market expected to grow by over 25% to nearly £1bn by 2022.
Peter Lagan, Kevin’s son and a director of Lagan Investments, said: “The acquisition of Frame-Tech provides us with the opportunity to expand our timber frame representation into the North of England.
“Given the ever-increasing demand for off-site manufacturing, and the need to address the shortage of homes throughout the UK and Ireland, we intend to collectively grow our market share and consider further acquisition opportunities.”
Jamie Atkinson, MD of Frame-Tech Structures said: “This new investment by Lagan will allow us to take the business to the next stage, expanding both our product offering and geographical coverage.
“Having worked closely with Kevin and the Lagan management personnel over the past few months, we are very confident that our talented teams can work together to deliver value for money solutions for both existing and new customers.
“We also envisage exciting opportunities to work closely with the Lagan owned FastHouse operation.”