ST. CHARLES, MO – Wiegmann Associates has been ranked on multiple prestigious lists for its significant growth and position in the industry. Founded in 1995, Wiegmann Associates is a St. Louis-based mechanical contractor that engineers and installs energy-saving HVAC solutions, refrigeration systems and automation controls for clients across the United States in a wide range of industries.
Wiegmann was named to the Engineering News-Record (ENR) Top 600 Specialty Contractors list and was recognized as one of the St. Louis region’s 50 fastest-growing private companies, largest area employees, largest mechanical contractors, largest engineering firms, and largest businesses in St. Charles County in five separate rankings published in the St. Louis Business Journal. Rankings were based on the firm’s $78 million 2024 revenue, year-over-year growth and the team’s size of 118 employees.
“We are extremely proud that our team continues to innovate and earn the trust of our clients year after year,” said Grant Wiegmann, president of Wiegmann Associates. “Our dedicated employees and loyal clients are the fuel that drives our longevity and growth.”

Headquartered in St. Charles, Missouri, Wiegmann Associates is a national leader in design/build HVAC projects with specializations across several industries, including senior living, food and beverage distribution, warehouse, healthcare, commercial and industrial.

ABOUT WIEGMANN ASSOCIATES
Wiegmann Associates is a St. Louis-based mechanical contractor and a national leader in design/build HVAC projects. Since 1995, Wiegmann Associates has engineered and installed innovative, energy-saving and cost-efficient HVAC solutions, refrigeration systems and automation controls for clients in a wide range of industries, including senior living, food and beverage distribution, warehouse, healthcare, commercial and industrial. Wiegmann also provides 24-hour preventative maintenance programs and service in the St. Louis region. Wiegmann is ranked among the Top 600 National Specialty Contractors by Engineering News Record and is consistently ranked as one of the largest mechanical contractors in St. Louis by the St. Louis Business Journal. For more information, visit www.wiegmannassoc.com or call (636) 940-1056.