Limbach Holdings Inc is a commercial specialty contractor in the fields of heating, ventilation, air conditioning, plumbing, electrical, and building controls for the design and construction of new and renovated buildings, maintenance services, energy retrofits, and equipment upgrades. It operates in two segments: Construction, which involves new construction or renovation projects, primarily HVAC, plumbing, or electrical services; and Service segment, which provides maintenance or services primarily on HVAC, plumbing, electrical systems, and building controls directly for building owners and direct specialty contracting projects. The company derives the majority of its revenue from the construction segment.