Founded in 1963 by Clive Lewin, Bryon Grace and associates  and latterly taken over and forward by Clive and Bryon Isotemp (Heating & Ventilating) Limited was established with a commitment to quality workmanship, reliable service, and lasting customer relationships. What began as a local ductwork and ventilation specialist in High Wycombe has grown into one of the region's most respected family-run businesses.

For more than six decades, Isotemp has been at the forefront of the ductwork industry, delivering bespoke ventilation solutions across commercial, industrial, healthcare, education, residential, and public sector projects. Throughout this time, the company has remained true to the values on which it was founded – integrity, craftsmanship, and a dedication to exceeding client expectations.

In 1994, the second generation of the Lewin and Grace families took the reins, building upon the strong foundations laid by the founders. Under their leadership, Isotemp expanded its manufacturing capabilities, invested in new technologies, and strengthened its reputation as a trusted partner to contractors, consultants, facilities management providers, and end users throughout the UK.

A landmark moment in the company's history came in 2024 when the third generation assumed ownership. Today, Ryan Lewin and Jack Needham proudly lead the business, continuing a family legacy that spans more than 60 years. Combining traditional values with modern project delivery, dedicated project management, in-house estimating expertise, and a commitment to innovation, they are driving Isotemp forward while preserving the principles that have defined the company since day one.

Operating from our headquarters at Loudwater Mill in High Wycombe, Isotemp continues to manufacture, supply, and install high-quality ductwork systems for projects of all sizes. As we look to the future, our focus remains unchanged: delivering exceptional quality, building long-term partnerships, and maintaining the trust that generations of customers have placed in our family business.

Three Generations. Since 1963. Built on Quality, Driven by Family.