2025 Forge Prize winner grows a new 'vertical community' using the latest innovations in steel

The grand prize winner of the $10,000 Forge Prize for 2025 has been announced by the American Institute of Steel Construction as a scheme turning an underutilized space in dense urban neighborhoods into new communities in New York City.

Architect Ho-gyeum Kim of the New York firm Carlos Zapata Studio was given the prize for his scheme called "Growing Rowhouses." It creates a new, vertical community consisting of duplex units with semi-private outdoor yards from the rear yard spaces of a typical rowhouse block. Kim is working in his tenth year at the firm after graduating from the Columbia GSAPP in 2015.

Supported by an 18-foot grid, the height of the new rowhouses can change according to allowable zoning and come complete with other outdoor communal spaces such as a rooftop terrace and running track. Curved hollow structural sections are used to create a "cohesive look" across external stairs, the roof structure, and trellis extensions. Steel cables are then introduced to either side of the central structural core to stabilize the building’s lateral movement.

"Steel is the most viable solution to achieve the minimal touchdown in the centerline of the blocks," Kim described. "A prefabricated, modular construction system taking full advantage of steel’s unique potential to facilitate economical, rapid erection--and steel’s unique recyclability and circular supply chain add an additional layer of sustainability while preserving the existing rowhouses."

"We think it’s a robustly developed proposal with a timely architectural premise and a clear idea about how and why steel will be used to support the concept," editor Matthew Marani said, speaking for the 2025 Forge Prize jury. "It has a well-considered implementation strategy, including coordination with zoning and planning constraints, market demands, and erection efficiencies. It also fits neatly into new approaches to zoning within the Department of City Planning, specifically the larger City of Yes policies that are being rolled out."

Kim is the prize's eighth winner. The Forge Prize was founded in 2018 in order to recognize emerging architects, educators, and graduate students for design concepts that embrace steel as their primary structural component. 

The two runners-up for the 2025 competition were "Transforming Galvanized Sheetmetal Waste Streams into a Modular Living Wall Planter System" by Texas A&M’s Ahmed Ali and "Pedestrian Bridge of Echo Lake" by Kaikang Shen.