Alterra Property Group identified 17 Market West, an 18-story high-rise in the heart of the Market West neighborhood, as the prime candidate for the largest office to residential conversion in Philadelphia.
Challenge
Converting an existing office tower into a modern residential community required reimagining the building’s structure, façade, and floorplates while respecting its mid-century heritage. The design needed to maximize natural light, create desirable living environments, and introduce amenities that would support contemporary urban lifestyles.
Solution
Working within the existing structure, the design team preserved portions of the original Indiana limestone façade while introducing taller windows and a new vertical expression that enhances natural light and city views. The building accommodates 299 one- and two-bedroom residences alongside an extensive collection of wellness-focused amenities, including a rooftop saltwater pool, fitness and yoga facilities, sauna, cold plunge pool, golf simulator, and multipurpose sports courts.
Outcome
Well-connected to Philadelphia’s transit network, 17 Market West maximizes existing infrastructure while supporting urban regeneration and reducing embodied carbon through adaptive reuse. The project establishes a forward-looking model for revitalizing city cores, bringing new housing, amenities, and street-level activity to a prominent downtown location.
The conversion introduced 299 one- and two-bedroom residences within a former 18-storey office tower, making it the largest post-pandemic office-to-residential conversion in Philadelphia.
17 Market West is the largest post-pandemic office to residential conversion in Philadelphia—a bold response to the growing demand for housing in urban centers and the realities of hybrid work. Alterra Property Group identified the 18-story high-rise in the heart of the Market West neighborhood as a prime candidate for conversion, creating a Class A mixed-use residential community with wellness at its core.
Originally built in 1957, the building’s exterior has been redefined while honoring its mid-century heritage by preserving portions of the original Indiana limestone. Working within the existing structure, the design team cut limestone spandrels at the floor lines to introduce taller windows and add vertical expression to the formerly horizontal elevation. A sleek metal channel system ascends the full height, drawing the eye upward to the signature sky frame—an extension of existing columns that captures unparalleled city views. This approach creates a distinct bottom, middle and top articulation, with a modern emphasis on spacious, light-filled interiors.
A balance of serenity and luxury defines 17 Market West. Working with the building’s long rectangular floorplates, the design team created 299 spacious one- and two-bedroom layouts with upscale finishes and built-in desk nooks. These residences are complemented by an extensive collection of resort-style amenities that elevate daily living and reflect a commitment to health and wellness.
On the rooftop, the signature saltwater pool invites residents to unwind. Cabanas, sunset lounges with fire pits, an outdoor screening area, BBQ grills and a dedicated dog run transform the rooftop into a private urban retreat.
The lower levels function as a vibrant fitness and lifestyle destination. Residents can recharge in the sauna and invigorating cold plunge pool, or stay active in the well-equipped fitness center, yoga rooms and golf simulator. Multipurpose courts for basketball and pickleball—connected to the Center City Pedestrian Concourse—make 17 Market West the ultimate urban destination to live well. Ground-floor retail and a four-story parking garage with EV-charging stations anchor the community.
Well-connected to Philadelphia’s Suburban Station, regional rail and underground concourses, 17 Market West maximizes the city’s existing infrastructure, supports urban regeneration and reduces embodied carbon—securing its place as a forward-looking model for revitalizing city cores.
