30 E. 60th Street
ADG designed a unique framing system for 12-story steel structure addition on top of an existing 15-story occupied commercial building in midtown New York City. The new 12 story addition of 45,000 SF building is supported only by two concrete towers within the light wells of the existing building and is supported by new foundations independent of the existing building. Vertical post-tensioning and rock anchors are used to control the horizontal movement of the building. All work was completed without any disruption to the existing tenants occupying the existing floors.