Phoenix Sky Harbor is in the middle of a major expansion play, adding a six-gate concourse onto Terminal 3 while keeping the terminal open and planes cycling through the gates. The roughly 173,000-square-foot addition, now estimated at about $368 million, is aimed at boosting capacity and is slated to open in fall 2027.
McCarthy Building Companies is leading construction, with HOK and DFDG Architecture on design, according to McCarthy Building Companies. Industry coverage reported that the firm and airport rolled out the project in spring 2025 as a six-gate, 173,000-square-foot effort meant to ease peak-period crowding at Terminal 3, and Facilities Dive documented the initial announcement and early site work.
More recent reporting digs into how crews are pulling this off while passengers stream through the building. As detailed by the Phoenix Business Journal, project managers and engineers say the scope and cost have evolved as on-site surprises popped up, and the outlet lays out the playbook they are using to avoid disruptive shutdowns.
Keeping flights and traffic moving
To keep passenger headaches in check, most of the heavy lifting is scheduled for off-peak hours and short overnight closures. The City of Phoenix has warned that eastbound Sky Harbor Boulevard has been shut down overnight at times so crews can install support structures and handle major crane work, and officials have been nudging drivers toward the 24th and 44th Street PHX Sky Train® stations as alternate access points. City of Phoenix travel advisories have carried the main public alerts about those traffic changes.
Steel, welds and local supply chains
Engineers describe the job as a carefully sequenced series of heavy lifts and staged assemblies. Many steel members are cambered, cut into pieces that can actually be moved through the site, then mechanically welded back together in place so crews do not have to shut down big chunks of the terminal at once. According to the Phoenix Business Journal, the program calls for more than 2,200 tons of structural steel, includes beams that weigh tens of thousands of pounds each, and some welds have taken more than 40 hours to finish…