The repurposing of One Milk Street, Boston

Located in Boston’s Historic Newspaper Row District and at the location of Benjamin Franklin’s birth, One Milk Street is composed of three connected buildings: the Boston Transcript Building (circa 1873), the Boston Post Building (circa 1874), and a reinforced concrete connector building from the 1930s (Figures 1 and 2). These three buildings, as with many mass masonry and timber buildings of this age, have had numerous modifications over their 100+ years. The current rehabilitation project encompassed a full building renovation with structural alterations to create mixed-use upper-floor offices and retail space on the ground floor. As Engineer of Record (EOR) for the renovations, Simpson Gumpertz & Heger (SGH) performed a broad range of scope including, but not limited to, evaluation of the existing structural components of the building to determine the level of code-triggered structural upgrades; development of a procedure for in-situ proof load testing of the existing heavy timber floors; and design of new structural components such as new elevator cores, egress stairs, a two-story mechanical penthouse, a new entrance canopy, and new concrete sidewalk vaults. This multifaceted project highlights the challenges inherent in structurally retrofitting 19th-century buildings.