The “Growing Rowhouses” concept, winner of the 2025 Forge Prize, reimagines urban housing through a bold integration of steel’s structural versatility and modular design principles. Conceived by Ho-gyeum Kim of Carlos Zapata Studio, this proposal addresses housing shortages in dense cities like New York by transforming underutilised rear yards in rowhouse neighbourhoods into vibrant, vertical duplex communities.
At the heart of the concept is an 18 ft structural grid, a dimension carefully chosen to align with the width of typical New York rowhouse lots. The framework uses prefabricated steel modules manufactured offsite, enabling rapid, cost-effective assembly with minimal disruption to existing structures. By using steel’s high strength-to-weight ratio, the design achieves slender profiles, allowing for maximised usable space without compromising stability.
The project employs steel cables to stabilise the vertical units, reducing the need for deep or invasive foundations. This tension-based approach is complemented by curved hollow structural sections, which seamlessly integrate stairs, roof elements, and trellises into the overall form. These sections are not only structurally efficient but also enhance aesthetic cohesion, underscoring steel’s capacity to be both a technical and architectural medium.
Steel’s recyclability and adaptability are central to the project’s sustainability goals. By limiting foundation work and employing modular steel elements, the design significantly reduces construction waste, site disturbance, and embodied carbon. The approach also allows for flexibility, units can be reconfigured, expanded, or removed as community needs evolve, highlighting steel’s reusability in a circular construction economy.
While conceived for New York’s housing market, the “Growing Rowhouses” framework offers a scalable solution for cities worldwide facing land scarcity and densification challenges. Steel’s combination of precision fabrication, long-span capabilities, and ease of modular connection makes it ideal for similar infill projects in London, Tokyo, or São Paulo, where unused urban pockets could be reimagined as housing.
By combining structural steel innovation with thoughtful urban planning, “Growing Rowhouses” showcases steel as more than just an industrial material, it is a catalyst for adaptable, sustainable, and community-focused architecture in the 21st century.
