Sustainable Investments Ltd (Sustainable Investments), a UK group operating across domestic green retrofit, energy services, building products and smart technology, has welcomed Bridges Fund Management (Bridges) as its investment partner to help accelerate its growth and expand its impact across housing and the wider built environment.

Funds managed by Bridges have purchased a significant minority shareholding (24%) in the group’s newly formed ultimate parent company. Derek Horrocks remains chairman and the majority shareholder, retaining overall control and continuing to lead the group alongside the existing business leadership teams.

Millions of UK households live in homes that are cold, damp and expensive to heat, leaving many in fuel poverty and exposed to rising energy costs. The Sustainable Investments group – which comprises Sustainable Building Services, Sustainable Energy Services, Permarock and Sustainable Smart Technologies – connects energy advice and design with retrofit delivery, building products, clean heat, renewable energy and digital monitoring, enabling clients and customers to access an integrated service or specialist expertise for individual projects. The group recorded turnover of £70 million in its latest published accounts (2025).

The partnership will support the group’s medium-term plans to develop its existing businesses, enter complementary markets and pursue selective acquisitions and commercial partnerships. It aligns Sustainable Investments’ focus on quality, people and lasting customer relationships with Bridges’ approach to growing impact-led businesses, where commercial success creates the opportunity to extend positive social and environmental outcomes.

Derek Horrocks, chairman of Sustainable Investments Ltd, said:

“The success of our businesses is down to our people and the trusted relationships we have built with our clients, customers and partners. From our family-business roots, my ambition has been to build lasting businesses that provide worthwhile careers and make a positive difference to homes, lives and communities.

“Being sustainable means building businesses that people can rely on and giving our teams opportunities to develop. As we grow, we can improve more homes and buildings, help more households facing fuel poverty and support the skills and local businesses needed to keep making a difference over the long term.

“I have chosen Bridges because they share that ambition and the values behind it. They understand that commercial success and positive impact go hand in hand, and their experience, wider team and relationships will help us accelerate our growth and deliver my vision for the group. Our teams have built a strong business, and this partnership will help us extend the difference we can make even further.”

Bridges is a specialist sustainable and impact investor with more than two decades of experience. Its wider team will bring expertise in business growth, investment and impact, while its portfolio and relationships offer opportunities for shared learning, complementary services and commercial partnerships. Bridges’ specialist impact team can help the group measure and improve outcomes, using evidence to guide business development and extend the benefits of its work for people and the environment.

Charlie Edwards, partner and co-head of inclusive growth at Bridges, will join the newly formed group board, led by Derek Horrocks. He brings extensive experience of supporting entrepreneurial businesses and will contribute directly to the group’s development alongside the wider Bridges team.

Charlie Edwards, partner and co-head of Inclusive Growth at Bridges, said:

“We’re delighted to be partnering with Sustainable Investments, a very impressive company that shares Bridges’ commitment to delivering exciting commercial growth in markets with high social impact. There is a clear opportunity for the group to scale its offering and expand its impact in the coming years, building on its outstanding work to date. I look forward to working closely with Derek and the rest of the team to support these ambitious growth plans, drawing on the broader Bridges team’s extensive experience of value creation and impact management.”

Sustainable Investments’ work responds to five interconnected challenges: fuel poverty, the cost of living, the housing crisis, energy security and climate change. Its businesses deliver energy efficiency, renewable energy and clean heat improvements to thousands of households and buildings each year.

Improving energy efficiency can make homes more affordable to heat, reduce exposure to energy price pressures and help people live more comfortably, while supporting better health and lower carbon emissions. The group’s wider societal contribution includes employment, skills development and opportunities for local supply chains, helping communities participate in the transition to a lower-carbon economy.

Domestic green retrofit remains central to the group’s plans, alongside opportunities across social and private housing, new build and refurbishment, low- and high-rise buildings, commercial and industrial premises, education, healthcare and public buildings. Across these markets, better building performance and reliable data can help owners and occupiers reduce energy waste, manage costs, improve indoor conditions and make more effective use of their buildings.

The group’s operating businesses retain their legal identities, brands, leadership, directors, management and operational teams. Existing contracts, service commitments and customer contacts remain unchanged as a result of the investment.

Sustainable Investments Ltd was advised on the transaction by DWF as legal adviser, RSM UK as tax adviser, and Rothschild & Co as financial adviser, with vendor assistance provided by Grant Thornton. Bridges Fund Management was advised by Addleshaw Goddard as legal adviser, CIL as commercial due diligence adviser, Deloitte as tax adviser, and Interpath as financial due diligence adviser.