Business Details
50+ Years
experience
Emergency
services
Your Trusted Mechanical Contractor in Milwaukee
Since 1932, J.M. Brennan has established itself as Milwaukee's most trusted mechanical contractor, delivering comprehensive solutions for HVAC, plumbing, and fire protection systems. Our team of 40 skilled technicians combines decades of collective experience with advanced methodologies like Building Information Modeling (BIM) and prefabrication to ensure precision in every project. We specialize in design, build, and service phases, offering 24/7 emergency response, preventive maintenance, and equipment replacement tailored to client needs. Our on-site maintenance program provides dedicated technicians who develop deep familiarity with client facilities, supported by our full engineering resources.With a legacy spanning 93 years, we maintain a relentless focus on quality workmanship, innovative problem-solving, and long-term client relationships. Our service extends across Southeastern Wisconsin, including Milwaukee and Madison, where we operate from strategically located offices. Every project reflects our commitment to technical excellence, operational efficiency, and unwavering customer support, ensuring systems remain reliable and future-ready.
Services
HVAC Services
Plumbing Solutions
Fire Protection
Design & Build
Preventive Maintenance
Emergency Repairs
On-Site Maintenance
Equipment Replacement
BIM Services
Prefabrication
Details
- Year established: 1932
Highlights and features
- We offer 93 years of specialized mechanical contracting experience
- Our team includes 40 highly trained HVAC, plumbing, and fire protection technicians
- We provide 24/7 emergency service with real-time dispatch capabilities
- Our on-site maintenance program offers dedicated facility-specific technicians
- We implement preventive maintenance strategies to maximize system longevity
Services
HVAC Services
Our HVAC division designs, installs, and maintains heating, ventilation, and air conditioning systems for commercial and industrial facilities. We offer complete system upgrades, energy-efficient installations, and emergency repairs. Our technicians use advanced diagnostic tools to ensure optimal performance and energy efficiency across all climate control systems.
Plumbing Solutions
We provide comprehensive plumbing services including system design, pipe installation, leak detection, and emergency plumbing repairs. Our team handles both residential and commercial projects with specialized expertise in industrial piping systems. We use modern trenchless technology and video inspection equipment for minimal disruption during repairs.
Fire Protection
Our fire protection services include sprinkler system design, installation, and maintenance for commercial buildings. We offer code compliance inspections, system upgrades, and emergency repair services. Our technicians are certified in fire suppression system maintenance and NFPA standards compliance for maximum safety assurance.
Preventive Maintenance
We develop customized maintenance plans to extend equipment lifespan and prevent unexpected failures. Our program includes regular system inspections, performance testing, and component replacements. We use predictive maintenance technologies to identify potential issues before they cause operational disruptions in HVAC, plumbing, and fire protection systems.
Emergency Repairs
Our emergency response team provides immediate assistance for critical mechanical failures 24 hours a day, seven days a week. We handle urgent HVAC breakdowns, plumbing emergencies, and fire system malfunctions with rapid dispatch and on-site problem resolution. Our technicians carry specialized equipment to address urgent issues promptly.
Questions
What services does J.M. Brennan offer?
We provide comprehensive HVAC, plumbing, and fire protection services including design, installation, preventive maintenance, emergency repairs, and 24/7 on-site support.
Do you provide emergency service outside regular hours?
Yes, our 24/7 emergency service dispatches trained technicians for urgent HVAC, plumbing, or fire protection issues at any time.
What areas do you serve?
We primarily serve Southeastern Wisconsin, including Milwaukee and Madison, with strategically located service centers for rapid response.
How does your on-site maintenance program work?
We assign dedicated technicians to client facilities who receive ongoing training and support from our full engineering team for personalized service.
What sets J.M. Brennan apart from competitors?
With 93 years of experience and 40 specialized technicians, we combine technical innovation with personalized service and 24/7 emergency readiness.
Do you handle both new installations and system maintenance?
Yes, we offer complete lifecycle services from system design and installation to preventive maintenance and emergency repairs for all mechanical systems.
Reviews (5)
Eric Gould
Jan 15, 2022
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Using cutting-edge techniques, first-rate materials, and experienced professionals, J M Brennan delivers quality work on time and on budget.
To The Max
Oct 26, 2020
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Coming from a 18 wheeler. I feel they get more straight truck traffic. just going off their setup! It took them about 20 minutes to get 3 pieces off the trl.
Andrew Byrne
Nov 03, 2019
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I have worked with JM Brennan on many projects and their dedication to customer service is top notch! They have developed a culture at their organization that is second to none in the Mechanical Contractor space. Their prices are fair and transparent and the staff does a great job of presenting the appropriate sense of urgency!
Amy Baisden
Jun 01, 2019
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Journeymen that work there are great, but Brennan sends you a lump sum bill and won't respond to any questions regarding it. I have tried for over 4 months to pay a bill, but I get a different answer every time I ask. I sent a letter to one of the owners, again trying to resolve the $500 plus bill, but never got a response. Horrible customer service. It's too bad as the journeymen that come out for service have always been great. Other tenants in our building downtown also complain about they feel they have been overcharged many times. We have a great HVAC contractor in Brookfield that we'll have to use in the future.
Rageman
Sep 14, 2018
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I have worked here for 3 years and it is truly an amazing place. Everyone is super friendly and helpful. The pipe and plumbing fabrication shops are exceptional, and the sheet metal shop is superb. Oh! Don't me get started on the shop warehouse. The shop manager is hands down one of the kindest, chrasmatic, professional, hardworking people I have had the pleasure of having him into my existence. Too darn bad the scale stops at 5! It should be infinity because the longer you are there the better the experience gets. Thank you JMBrennan, you have brought a new light into my life.
