New York design firm LOT-EK is known for incorporating recycled industrial materials—shipping containers, truck beds, even airplane fuselages—into its projects. So when Maurice Russell and Jorge Fontanez asked their friend Giuseppe Lignano, a principal at the firm, to renovate their 1,100-square-foot apartment in New York’s East Village, it came as little surprise that Lignano hauled in a truckload of recycled commercial doors.

The apartment had issues. In the mid-1980s, the building co-op combined each floor’s two narrow units into single dwellings encircling the central staircase, which resulted in wasted space, awkward connections, and dark interiors. In 2009, Russell and Fontanez gave LOT-EK three requirements for their renovation: Maintain the apartment’s circularity, bring more light into its middle, and maximize every inch for storage.

Lignano and his LOT-EK partner, Ada Tolla, put their industrial aesthetic and upcycling expertise to work. “We wanted to turn the problem on its head so that the forgotten and least-interesting areas—the two dark corridors—became the most important, most beautiful spaces,” Lignano says. With the help of contractor Andreas Scholtz of Craft Workshop, they tracked down 63 reclaimed commercial steel doors from Build It Green! NYC and built two tunnels through the apartment. What was formerly dead space is now packed with action. “We compressed everything functional or mechanical into the middle portion so the living room and bedroom could be open spaces,” Lignano says. “It was a puzzle—and a bit of a masterpiece—how we wedged everything in.” Now there’s a brightly lit place for everything.