One Madison Avenue

One Madison Avenue is undergoing a 1.4 million SF, 27-story office expansion to modernize the space into a state-of-the-art, Class-A office building next to Madison Square Park. The ambitious adaptive reuse project includes updates to the podium and the addition of a tower with over one acre of outdoor space and terraces. The building will provide open, airy interiors with flexible plans, efficient spaces, and a projected LEED Gold v4.0 rating. Langan performed a Phase I Environmental Site Assessment, oversaw the soil and rock disposal to confirm operations followed applicable regulations, and assisted the design team with the stormwater drainage system, site grading, and site utility connections. We also secured the required agency permits, conducted a geotechnical exploration program, guided the foundation and excavation support design, and provided construction inspections.