Grunau Company

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Claim This BusinessAbout Grunau Company
Grunau Company operates as a mechanical systems contractor based in Oak Creek, Wisconsin, within the greater Milwaukee metropolitan area. The business holds a 3.2-star rating derived from 13 customer reviews, reflecting a mixed client experience. Service operations extend across southern Wisconsin, covering communities from Madison westward to Green Bay northward, with additional project work spanning multiple states. Grunau functions as a union contractor affiliated with APi Group and maintains continuous availability with 24/7 emergency service capability throughout all operating days.
The contractor distinguishes itself through integrated project delivery methodologies and building information modeling capabilities, enabling collaborative planning from initial concept through final commissioning. Their portfolio encompasses mechanical systems engineering encompassing HVAC, plumbing, process piping, electrical infrastructure, refrigeration, and underground site utilities. The organization maintains in-house sheet metal fabrication and a dedicated pipe and weld shop, allowing for specialized custom component fabrication rather than outsourcing critical manufacturing phases. Their operational philosophy incorporates lean construction principles and safety culture frameworks, positioning the business for commercial and industrial projects requiring coordinated multi-trade mechanical systems installation.
Customer feedback reveals polarized service experiences. One reviewer documented an interaction involving a company driver in Kansasville that they characterized as unprofessional, while another detailed a same-day service scenario where the team arrived promptly during a critical heating or cooling emergency. Positive reviews specifically reference knowledgeable and helpful technicians who delivered quality workmanship, with Sandy Rapant noting the company's dependability and Greg Luna describing the staff as friendly and accommodating. These accounts suggest service quality may vary by specific job scope and assigned technician.
What Customers Say
Among 13 reviews, 2 reviewers awarded 5-star ratings praising dependability and knowledgeable technicians, while 2 reviewers gave 1-star ratings citing specific interaction concerns. The 3.2-star average reflects polarized sentiment, with positive feedback focusing on quality work and negative feedback targeting isolated service encounters.
Working Hours
| Sunday | Open 24 hours |
| Monday | Open 24 hours |
| Tuesday | Open 24 hours |
| Wednesday | Open 24 hours |
| Thursday | Open 24 hours |
| Friday | Open 24 hours |
| SaturdayToday | Open 24 hours |
Services
HVAC Installation & Repair
Heating, ventilation, and air conditioning systems installation, maintenance, and emergency repair services for commercial and industrial applications.
Plumbing Services
Complete plumbing system design, installation, and repair for commercial buildings, including medical gas piping specialties.
Process Piping
Specialized piping systems for industrial manufacturing, chemical processing, and specialized facility requirements.
Electrical Systems
Full electrical installation and infrastructure services for commercial and industrial mechanical systems projects.
Refrigeration
Commercial and industrial refrigeration system installation, maintenance, and emergency service for cold storage and process cooling applications.
Sheet Metal Fabrication
In-house custom sheet metal component fabrication allowing precise dimensional control for ductwork and specialty enclosures.
Underground Utilities
Site utility infrastructure installation including underground piping, electrical conduits, and associated ground-level mechanical systems.
24/7 Emergency Service
Round-the-clock emergency dispatch for urgent mechanical system failures requiring immediate professional response.