The Glasgow-based energy services firm was selected for the index out of the 5.6 million firms that were analysed. Union Technical is a family run business established by directors Owen Coyle and Michael Sweeney in 2014, later joined by Owen’s sister Suzanne.

The founders recognised a gap in the market for an all-encompassing service for energy efficiency renovations. It works with homeowners, tenants, local authorities, social and private landlords, and commercial businesses to deliver a broad range of energy saving services throughout the UK. 

This year, Union Technical is celebrating its 10th anniversary. Over the last decade it has developed from its small family run origins to a company of more than 100 people and projecting a turnover of £44 million by the end of 2024.

After completing an expansion to its Glasgow-based headquarters which effectively doubled the size of its premises, and being shortlisted for several prestigious awards, this year is on track to be the most successful to date for Union Technical.

Its success follows a period of significant development and growth, with the firm recognised at the 2024 Energy Efficiency Awards for its Highland Council project, Energy Efficient Scotland: Area Based Scheme (EES: ABS), which delivered large-scale energy efficiency measures across the North of Scotland.

Michael Sweeney, director of Union Technical, said: “After a decade of building our business to the success it is today, it’s fantastic to be recognised as one of the UK’s fastest growing firms.

“This and the recognition we have received from industry awards is a testament to our talented team and the work they carry out to make people’s homes across the UK more energy efficient and cheaper to heat.

“We look forward to growing our business further over the next 10-years, continuing to deliver innovative energy-saving solutions and contributing meaningfully to the UK Government’s vision for a greener and more energy-efficient country.”