The Architectural Team (TAT) has completed a mixed-use tower in Boston featuring the city’s first sky lobby. The Raffles Boston Hotel & Residences features a 400-foot curved glass form and is described by the team as a “sophisticated new skyline statement within a challenging and historic context.”

The 35-story high-rise comprises 146 homes, 147 hotel guestrooms, and 16 amenity spaces. To compensate for the site’s narrow plot, the tower’s design sees a cantilever at the fourth-floor extent over the adjacent historic University Club to support the upper 29 stories, with a further cantilever occurring at the 17th floor.

In addition to increasing the internal area of the tower, the cantilevering approach forms a distinctive design element of the scheme’s exterior, “granting the tower a contextually scaled street presence while also allowing the building to express itself as a sculptural form on the upper levels,” according to the team. To deliver the cantilevers, a series of six-foot-wide caissons were drilled 150 feet into the bedrock, followed by 1.5 million pounds of steel plate girders and more than 1,428 cubic yards of concrete for the building’s seven-foot-thick mat slab.

Meanwhile, to differentiate itself from the angular form of the adjacent Hancock Tower, the design team developed a curved mass for the Raffles Tower informed by wind loads. A glass curtain wall clads the tower with a dark shade to contrast the lighter hue of the Hancock Tower.

Inside, the scheme’s hotel begins with a 17th-floor Sky Lobby and a spiral staircase spanning three levels. Among the 16 amenity spaces in the tower are restaurants, bars, lounges, and a 3,000-square-foot ballroom, while a 4th-floor gym is accompanied by a 66-foot indoor pool. The hotel interiors have been designed by Stonehill Taylor, with Rockwell Group designing the residences, fitness center, spa, and residential amenities, and Studio Paolo Ferrari designing the Long Bar venue.

“Raffles Boston Hotel & Residences represents an ambitious mix of uses, with a design that is particularly sensitive to its surrounding context — the historic Copley Square and iconic Hancock Tower,” says Michael E. Liu, senior partner and design principal at TAT. “The exterior is sculpturally distinctive and explicitly designed to set itself apart from the neighboring buildings. Our aim was to bring new design energy to the skyline, a fresh vitality to the area’s street life, and capture the distinctive personality of Boston while honoring the impeccable luxury and legendary hospitality synonymous with the Raffles brand.”

News of the scheme’s completion comes weeks after SOM shared photos of their new US DOT Volpe National Transportation Systems Center in nearby Cambridge. Earlier in December, Harvard GSD released details of their planned Gund Hall renovations, while French 2D completed a Boston co-housing complex grounded in community connections.