The Equinox Fitness Club located at 225 Franklin Street in Boston, Massachusetts sits in the heart of the downtown market. The Franklin Street building was originally the home of State Street Bank. Equinox now occupies the first floor space and the concourse level below. 

The first floor was an example of a by-gone banking era with grand vaulted ceilings, and large expanses of windows. An existing spiral stair, which was a wonderful example of modernist architecture, connected the two floors. Although the original stainless steel vault door on the concourse level may have been the most unexpected surprise. The circular pattern on the door became the inspiration for the design and the new club architecture. S3 Design was hired by Equinox to develop the design and set the club feel through schematic design; and were subsequently retained through Design Development, Construction Documents, and Construction to work with the Base Buildings Architect of Record providing guidance and design continuity.