408•347•3400 - Office Phone
408•347•3500 - 24/7 HVAC Service
408•347•3533 - 24/7 Plumbing Service
Request for Service Online

From vision to implementation.

History of innovation. Founded in the early years of the Silicon Valley technological revolution, Therma Corporation has made a significant impact on the Bay Area’s mechanical industry. We performed the original mechanical work for cleanroom and manufacturing areas of the founding semiconductor companies and we continue to be on site for many high-tech leadership firms.

In 1998, then-President Bill Clinton held a roundtable at Therma Corporation to learn more about its “work smart” culture and history of success. And in 2013, our founders, Joe and Nicki Parisi, were awarded honorary Doctorates of Humane Letters from San Jose State University for their impact on the innovative growth of the Bay Area’s mechanical industry.

Talent and experience. Therma Corporation employs the most highly trained and experienced designers, installers, and service technicians in the field. Our 700+ employees include more than 600 craftsmen from the pipefitter, plumber, and sheet metal unions, making us the largest union employer for mechanical construction in the Bay Area. Because of our consistent volume, we’ve had a very low turnover in our core trade personnel. As a result, our craftsmen are highly loyal, better trained, and of a higher technical caliber than at many other firms.

Longevity and stability. We have built more electronics, semiconductor, and biopharmaceutical facilities than any single mechanical contractor in Northern California. And we’ve completed air conditioning or plumbing systems in local office and public buildings totalling millions of square feet.

Cutting-edge technology. Our 280,000-square-foot headquarters in San Jose includes a 60,000-square-foot, ASME-certified fabrication shop – the most state-of-the-art duct fabrication and pipe prefab facility in Northern California, with automated systems, lasers, and the newest welding technology – which puts us far ahead of any competitor’s ability to design, fabricate, and install materials and equipment.

Our shops are supported by the latest computerized documentation and design systems available, including AutoCAD, Solid Works, Pipe Designer 3D, CAD duct, and Profile Master (PM 2000). And our accounting system is among the most advanced in the industry, tracking customer requirements and providing necessary documentation for our clients.


“It is always a pleasure working with Therma Corporation. On our project, we were presented with some difficult hurdles and challenges. I’m not sure how many people could have overcome them, but Therma Corporation’s exceptional mental toughness was on full display. Thank you for your patience and support throughout this project.”

Paul Burke - Manufacturing Engineer