COMFORT SYSTEMS USA INC

Comfort Systems USA, Inc., a Delaware corporation, was established in 1997. We provide mechanical and electrical contracting services. Our mechanical segment principally includes heating, ventilation and air conditioning ( HVAC ), plumbing, piping and controls, as well as off-site construction, monitoring and fire protection. Our electrical segment includes installation and servicing of electrical systems. We build, install, maintain, repair and replace mechanical, electrical and plumbing ( MEP ) systems through our 50 operating units with 190 locations in 142 cities throughout the United States. We operate primarily in the commercial, industrial and institutional MEP markets and perform most of our services in manufacturing, healthcare, education, office, technology, retail and government facilities. Substantially all of our consolidated 2025 revenue was derived from commercial, industrial and institutional customers and multi-family residential projects. Approximately 63.2% of our revenue was attributable to installation services in newly constructed facilities and 36.8% was attributable to renovation, expansion, maintenance, repair and replacement services in existing buildings. Our consolidated 2025 revenue was derived from the following service industries: Percentage of Service Activity Revenue Mechanical Services 73.3 % Electrical Services 26.7 % Total 100.0 % Industry Overview We believe that commercial, industrial, and institutional mechanical and electrical contracting generate annual revenue in the United States of approximately $700 billion.