24/7 Emergency Service: (414) 342-3829

Work Completed On Time by Experts

J.M. Brennan is the leading mechanical contractor for all projects from simple to complex. To earn that reputation, we’ve made an unparalleled investment in our people and our capabilities. We maintain a seasoned, experienced team with a detail-oriented focus and a commitment to quality work.

Our dedicated crew, including certified welders, steamfitters, sheet metal workers, plumbers, and service technicians, will ensure the timely completion of your next project.


Improves productivity, quality, schedule, and safety which in turn reduces costs.

Custom Solutions

J.M. Brennan's knowledge and experience is ideal for complex projects.