Connected by design, but the contrast in the appearance of these twins couldn’t be more pronounced | Photo: Starr Herr-Cardillo

Author’s Note: Last summer I moved to Philadelphia from my hometown, Tucson, Arizona, to pursue a master’s degree in historic preservation. As a newcomer to West Philly, where I live, once I got past the sheer size of the massive houses, with their wedding cake Victorian ornamentation and mighty turrets, I began to notice that most were clearly and deliberately split down the middle. As a transplant I found this quite peculiar. At first glance they look like huge single-family homes, but, upon closer inspection, they are actually two homes that diverged from a shared wall, a separation highlighted by a line right down the center. The combinations of contrast between the two halves are limitless, from completely different color schemes to variations in building materials, reconfigured porches and entryways, and retention or removal of various architectural features. I’ve never received more than a shrug pointing out this oddity to native Philadelphians. The concept has evolved and persisted over time, reaching near ubiquity and showing up later­­ in row houses and newer suburban developments. Over the past year, I have come to love it as a unique, regional quirk.

These divided homes began as a result of West Philadelphia’s development as an early streetcar suburb at a time when developers sought to emulate the spacious, rural appeal of country retreats, but with higher density and more affordable housing that would attract the upper-middle class. In order to create the atmosphere of a suburb full of rambling mansions, real estate speculators adopted the semi-detached building typology—what we commonly refer to as “twins”—that are essentially two single-family homes built side-by-side and designed to look like as a singular, comprehensive structure.

On walks through the neighborhood I’ve observed how, over time, owners have literally drawn the line between their houses, an action undertaken either consciously or without any substantial forethought. Sometimes the differences are subtle and sometimes they are dramatic. Finding and photographing the smallest nuances and variations, especially between seemingly identical houses, has become an ongoing game for me.

This kind of exaggerated delineation between two attached homes is a fascinating manifestation of the notion of private property. Often, they provide a kind of jumbled visual record of the original design, where you can jump back and forth between the two sides trying to decipher which original features still remain. Although each side may have started out as identical, after more than a century and a string of successive owners, it is extremely rare to find two sides of a twin that have physically evolved in exactly the same way.

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