Souter Investments, the private equity focused family investment office, has announced its backing of Duke Street in its acquisition of McAvoy, a provider of high-quality modular buildings and social infrastructure.
McAvoy marks Souter’s seventh deal with Duke Street, following its recent co-investments in ForLife Healthcare and AGITO Medical.
Founded in 1972, McAvoy designs, builds, and rents premium space solutions, ranging from temporary modular buildings to fully bespoke permanent buildings. McAvoy has extensive experience in supplying the health, education, pharmaceutical, and commercial sectors across the UK and Ireland.
This investment will increase the size and quality of McAvoy’s rental fleet, enabling the company to continue offering its customers premium, high-quality buildings delivered at pace and without the need for capital outlay.
McAvoy provides complete turnkey solutions that adhere to the same regulations as traditional buildings, but can be delivered up to 50% faster. Its modern, custom-built modules are typically more than 70% complete before leaving McAvoy’s 70,000 square-foot purpose-built manufacturing facility in Lisburn, Northern Ireland. This facility has the capacity to design and manufacture up to 1,200 modules annually, making McAvoy one of the largest modular building providers in the UK.
Headquartered in Lisburn, Northern Ireland, McAvoy has over 160 employees and offices in Dublin, Birmingham, Bristol, and London.
McAvoy has grown substantially in size and profitability, reflecting increased demand in the UK modular rental and sales market for premium, cost-effective, and sustainable buildings that are flexible and easy to deploy. The company’s rental division - which removes the need for customers to make substantial capital investments and provides them with ongoing maintenance and support - has been particularly successful.
Joe Thompson, Partner at Duke Street, commented: “McAvoy is a sustainable, well-capitalised and market-leading business that has a strong reputation for building premium modular solutions. In the last few years, the exceptional management team, led by CEO Ron Clarke, has successfully taken to market a new and differentiated modular product, SmartSpace, that exceeds building regulation requirements. Duke Street’s acquisition of McAvoy complements our long-held investment focus in essential social infrastructure services that provide the backbone to the economy.”
Maurice Shamash, Investment Director at Souter Investments, commented: ”It has been a busy 2025 with 6 new co-investments added to the portfolio so far. Our latest acquisition of McAvoy marks our 7th deal with Duke Street, in a partnership spanning 12 years.
“The pressures on aging infrastructure are well known, and McAvoy’s model of renting modular buildings for schools and hospitals offers valuable solutions. It boasts rapid deployment, financial flexibility and the ability to adapt quickly when capacity requirements change, combined with improved sustainability credentials. We are delighted to add another innovative, dynamic management team with award winning service and products to our portfolio and look forward to supporting Ron Clarke and his team execute their exciting growth plans.”
About Souter Investments
Souter Investments is one of the UK’s leading family investment offices, founded by Sir Brian Souter. Its team specialises in making private equity investments in unquoted companies, managing its capital in a supportive way that aligns the interests of investors, founders and management teams behind an agreed set of clear objectives.
A major beneficiary of Souter’s work is the Souter Charitable Trust, which supports projects engaged in the relief of human suffering in the UK and overseas.
Founded in 2006 with a sector-agnostic approach, Souter Investments has invested over £700m in more than a hundred unquoted companies to build a resilient and diverse portfolio of successful, valuable, and sustainable businesses that are category leaders in their chosen fields.
The McAvoy acquisition continues an active period of investment activity for Souter in 2025, including partnering with Sullivan Street in January on its investment in Zelus Sport, the exclusive Nike authorised global license for team sport; then continuing the relationship with Sullivan Street in April with its acquisition of TMS Ltd, a leading marine civil engineer and contractor; participating in Horizon Capital’s investment in ERA, a global leader in cost optimisation, insights and supply chain consulting; and partnering with Avera capital in its majority investment in MEL Aviation Components, a leading provider of aerospace components and supply chain solutions in the UK.
