This is a Total Small Business Set-Aside solicitation for a single firm fixed-price construction contract to perform comprehensive HVAC upgrades for Building 304 and Hanger 9. The contractor will provide all plant, labor, transportation, materials, tools, equipment, and supervision necessary for the work, from demolition and removal of old units through installation, commissioning, and integration with existing digital controls. Work will be performed over a 365-day period while the buildings remain occupied and operational, requiring careful coordination for utility shutdowns and access to secure areas. Performance will take place at Selfridge Air National Guard Base, MI 48045. The procurement is conducted in accordance with FAR Parts 12, 14, and 36, with an Invitation for Bids to be issued.