The ten-story Main Building Addition to Boston Children’s Hospital is unique both in terms of architectural effect and its structural design. Its curtain wall façade encloses one 60’ long cantilever was precisely placed over existing space and a 7.5’ long cantilever that provides cover for the Binney Street sidewalk. The addition includes twelve new short stay beds eight additional beds for the Emergency Department, an increase in radiology capacity, and addition to surgical areas and associated new inpatient support spaces. The new expansion also allows for as many as 44 single-bed inpatient rooms to meet the needs of future subspecialties.