The triple-wide 415-17 S. 15th St. was constructed as a single family home around 1860, which is pretty consistent with construction standards for mansions of the time, but feels extremely over the top these days. 419 S. 15th St. was built next door a couple years later, also as a single-family home, and is 20′-wide. This four-story building is objectively an amazing property, but we have to think that the original owners felt like paupers, compared to their neighbors to the north.

By the early 20th century, the properties were collectively being used as a group home by the Pennsylvania Society to Protect Children from Cruelty. This organization maintained ownership until quite recently, with the buildings most recently being used as offices and to support services for children. In 2023, the properties went up for sale, emerging as strong candidates for conversion back to residential.

Wouldn’t you know it, developers purchased the properties, paying a $2.75M price that might feel a little low at first glance. But if you dig into the properties a bit, you’ll see a complicated and risky approval process that likely brought the price down a bit. Not only are the buildings contributing in the Rittenhouse Fitler Historic District, but the parcels are curiously zoned for low density mixed-use, which severely limits any by-right development opportunities.

The first step is the Historical Commission, which has a full veto power over any desired alterations. The developers presented a plan to legally combine the two properties and turn them into a 32-unit apartment building. Thanks to the plans from Lo Design, we can see the renovation will include a mixture of removing non-historic elements, paired with the construction of additional floors over the existing structures, a two-story connector between the legacy structures, and new construction of an infill four story structure at the rear of the property.

After some back and forth, the Historical Commission gave their blessing to the project at the end of last year. With approval from the Historical Commission in hand, the developer’s next step is getting a zoning variance for the project. As we mentioned, the underlying zoning for this property is fairly restrictive, and the project needs variances for height, density, open area, and setbacks. The development team recently presented the project at a Center City Residents’ Association public zoning meeting, in anticipation of the ZBA hearing in May.

Assuming the ZBA gives the thumbs up, we’ll have a situation where buildings were built as residences, changed to offices, and will come full circle to change back to residences. It’s all part of the natural evolution of downtown Philadelphia, and our urban fabric is all the better for it. And if an office to residential conversion can pencil out for a complicated site like this one, we could be in store for some interesting Center City proposals in the coming years.