After more than three decades in the insulated glass market, British company Cleartherm Glass Sealed Units is delivering a blunt message to its peers: manufacturers that resist automation risk being left behind as production demands rise and labour pressures persist.
The Leicester-based IGU manufacturer, founded 37 years ago, says automation has reshaped both its output and its long-term outlook. Cleartherm’s recent production gains follow its decision to automate insulated glass unit manufacturing using Super Spacer® from Edgetech, part of the Quanex group, a relationship that now spans almost 25 years.
Managing Director David Laing credits that partnership with helping the business transition from manual processes to a more consistent, higher-volume operation. Where Cleartherm once produced between 300 and 400 units per week by hand, the company now manufactures more than 4,000 units weekly within a standard 8.5-hour shift.
According to Laing, the change has been as much about reliability as scale. Automation has brought repeatable standards across every shift, while access to Edgetech’s technical support has given the company confidence as volumes increased. The result has been steady expansion without sacrificing quality, an outcome he believes would have been difficult under a purely manual model.
Labour availability remains a defining challenge across UK manufacturing, and Cleartherm views automation as a practical response rather than a replacement for people. While skilled operators are still required, Laing argues that technology reduces dependency on hard-to-source manual roles and allows teams to focus on oversight and process control.
Sales Director Gareth Laing is equally direct when addressing other IGU manufacturers. Without investment in automation, he says, Cleartherm would not be operating at its current scale. For businesses with similar ambitions, he believes the choice is straightforward if they want to remain competitive.
From Edgetech’s perspective, Tony Palmer, Head of Sales, points to Cleartherm as evidence of what can be achieved through early adoption and long-term commitment to automated systems paired with proven spacer technology.
Cleartherm’s position leaves little room for ambiguity. In a sector facing cost pressures, workforce constraints and rising expectations, the company sees automation not as a theoretical upgrade, but as a practical requirement for sustained progress.
Why This Matters: Cleartherm’s shift underlines a structural reality for UK sealed unit manufacturing. Reliability increasingly depends on automated processes, while labour shortages make manual production harder to sustain. Firms that delay investment risk constrained capacity, inconsistent output and weaker resilience as market demands tighten.
