This is an Expression of Interest for HVAC upgrade services at the TAN-675 facility at the Idaho National Laboratory. The work involves removing old components, installing new equipment and controls, and ensuring compliance with standards. The performance location is within the laboratory's 890-square mile site boundary, where the Davis-Bacon Act and a Site Stabilization Agreement apply to construction work. The budget is not specified. This initial step will be used to identify vendors for a future Request for Proposal process.