David chipperfield's design for the more than 200,000-square-foot east building presents a contemporary counterpart to the museum’s neo-classical 1904 main building. awarded leed gold status by the u.s. green building council, the design organically links the two buildings, and a new grand stair provides a seamless transition between the main and the lower-level galleries and visitor amenities. museum visitors may use the fully accessible new entrance to the east building or the existing sculpture hall entrance to the main building, where the original floor plan has been restored as part of the expansion project.
The facade of the east building features floor-to-ceiling windows and 23 monumental panels of dark polished concrete, with highlights of missouri river aggregates. inside the galleries, innovative coffered ceilings made of light concrete provide abundant but controlled natural light, supplemented with artificial illumination which is managed by a computerized sensor system that automatically adjusts to changing light levels throughout the day. wide-plank white oak floors and stainless steel floor vents are designed to provide a distraction-free setting for the works of art.