In 2018, Heffron was selected to design and build the mechanical and plumbing systems for WMATA’s new headquarters at 300 7th Street SW — a full retrofit of a building stripped back to structural concrete for renovation. The primary challenge was the original 1960s ceiling heights, which left almost no room for conventional distribution.

Heffron engineered a low-profile Dedicated Outside Air System terminal unit integrated with a VAV air handler, fitting full mechanical capacity into a building envelope that standard approaches could not accommodate. Downtown road-closure coordination, adjacent rail constraints, and the complexity of a full headquarters retrofit made the job a clear example of the firm’s design-build problem solving in a demanding urban environment.