Grunau Company

Grunau Company is a full-service mechanical systems contractor. Our professional staff designs, installs and services HVAC, plumbing, process piping, electrical, refrigeration, fire protection, and underground utilities for any size commercial and industrial project. Our Grunau Metals division designs and fabricates structural and specialty metals. Since 1920, Grunau's name has been synonymous with a solid reputation, innovation, forward-thinking, creative solutions, customer focused, and built on values. Grunau is headquartered in Oak Creek, Wisconsin and has fire protection branches in Florida, Indiana, Ohio, and Pennsylvania.

Established in 1920.
In 1920, Paul J. Grunau established Grunau Company for plumbing and repair services. The business expanded into HVAC / piping in 1923, then fire protection in 1929 when Paul E. Grunau joined the business. In 1977, Grunau added structural & specialty metals to it capabilities. After 4 generations of Grunau's ran the company, it became part of the APi Group family of specialty contractors in 2006.