Buildner has revealed the results of its Under Bridge Affordable Housing Challenge, the 17th version of its Affordable Housing competition series, which focused on proposing design solutions to address housing challenges in cities around the world. This competition aimed to transform neglected areas under bridges, turning idle or empty spaces in sprawling cities into vibrant and thriving communities.
Participants were invited to select any "under the bridges" site globally, considering factors such as accessibility, available amenities, and how the proposed solution would integrate with the existing community or city. Designs needed to demonstrate adaptability, ensuring they could meet diverse needs while remaining cost-effective and sustainable. Buildner and its jury sought practical, scalable, and eco-friendly designs to revolutionize these overlooked spaces. The competition encouraged creative thinking and innovative housing solutions that challenge conventional approaches.
Buildner worked with an international jury panel to evaluate the received entries:
- Cas Esbach, Project Leader and Architect at MVRDV in Rotterdam
- Philippe Fouche, Director and Architect at South Africa-based SAOTA
- Avi Friedman, Professor of Architecture at McGill University and President of Avi Friedman Consultants, Inc.
- Samista Jugwanth, Associate and Shareholder at Zutari
- Luise Marter, Collaborator at KWY Studio in Lisbon
- Blake T. Smith, Associate and Senior Designer at BIG in New York
- Nicolas Sterling, Co-Founder and Director of Sterling Presser Architects and Engineers in Berlin
- Elke Sterling-Presser, Co-Founder and Director of Sterling Presser Architects and Engineers in Berlin
- Renyi Zhang, Senior Architect and Urban Designer at Perkins&Will
- Andreas Tjeldflaat, Founder of Framlab in New York and Bergen, Norway
Overlooked Urban Spaces
The spaces beneath urban bridges are often overlooked—shadowed, unused pockets within the cityscape. Traditionally, these areas have been relegated to practical uses like parking or storage, with little consideration for their potential as active parts of the urban environment. However, as cities grapple with increasing demands for housing and public space, these under-bridge areas are attracting new attention from architects and urban planners.
Design Opportunities
Rather than viewing these spaces as mere byproducts of infrastructure, some designers see an opportunity to repurpose them in ways that could benefit surrounding communities. The idea is to transform these underutilized zones into functional areas that provide affordable housing, public amenities, or green spaces. With careful planning and innovative design, these spaces could be integrated into the urban fabric, offering much-needed housing in central locations and creating new community hubs.
Architects are exploring ways to use the structural support of bridges to create modular housing units that fit neatly beneath the spans. Often located close to transit lines and central locations, these spaces offer a unique opportunity to develop affordable housing without consuming additional land. Beyond housing, there’s potential for pedestrian pathways, public art installations, and green spaces that could help connect neighborhoods and foster more cohesive urban environments.
Reimagining these spaces is not without challenges, but it presents a chance to rethink how cities use their limited space. As urban centers continue to grow, making use of every available inch—including the areas beneath bridges—could be key to creating more sustainable, livable cities. The challenge lies in finding ways to maximize benefits for the communities involved.
Projects
First Prize Winner + Buildner Student Award
Project Title: New Raft
Authors: Yujun Cai from China and the National University of Singapore
The selected site is in Jiuzhou Bay, within the Pearl River Estuary—a crossroads with numerous shipping lanes and a harbor for the Tanka people. According to the authors, the new Hong Kong-Macau bridge has disrupted the natural environment of the Tanka community, who have fished and lived on the water here for centuries. The design aims to create a "bottom-up" maritime community by using three elemental units based on the module of a typical Tanka fishing raft. The layout is intended to preserve the physical structure of existing communities, while the negative space beneath the bridge is transformed into a cultural area.
Second Prize Winner
Project Title: The HiveWay
Authors: Stephanie Julie Maignan, Qianhui Wang, Ogulnabat Jumayeva, Brian Tien, from B+H Architects & the Surbana Jurong Architecture & Design Council of Excellence, Canada
The Gardiner Expressway, once a symbol of 1960s futuristic urban planning, now separates downtown Toronto from Lake Ontario, creating polluted and unused spaces beneath it. As Toronto's population approaches 7 million, the demand for affordable housing in the downtown core is immense. The HiveWay proposes to transform a 2 km stretch of the Gardiner—from Lower Jarvis Street to east of the Don Valley Parkway—into vibrant, affordable housing. By utilizing the planned rerouting of this segment, the vision integrates housing directly with the infrastructure. Precast concrete box girders will be used for the new stretches, enabling faster, modular construction. The concept envisions housing cars within the girders' voids, leaving space above and below for residential units, mixed-use amenities, and green spaces. Hexagonal modules will accommodate soundproof, insulated housing units, while ground and intermediate levels will provide community services, retail, and recreational areas. The HiveWay aims to convert a relic of outdated urban planning into a sustainable, integrated development, revitalizing Toronto's urban landscape.
Third Prize Winner
Project Title: [0,0,-1] XYZ: Manhattan U-Housing
Authors: Hoyeon La, Seo Junhyeong , Jung Hyun Ji , Seonghyun Jeong from South Korea and Yeungnam University
XYZ: Manhattan U-Housing reimagines urban expansion by utilizing the space beneath the Manhattan Bridge. The bridge, supplied with water from the East River, powers a piezoelectric generator through traffic. Light ducts connect streetlights to residential areas, which include libraries, cafes, and shelters. This project addresses urban density and social stratification by creating U-shaped steel-frame units that integrate with the bridge, offering noise and vibration isolation. Each unit operates independently, avoiding interference with neighbors, and features manual elevators powered by human strength, which minimizes energy consumption while ensuring vertical mobility.
Sustainability Prize Winner
Project Title: Living Under a Common Roof - Reinterpreted tube houses
Authors: Thu Nga Nadine Do from Austria and TU Wien
Clay, a key material in traditional Vietnamese architecture, is central to the tube houses featured in "Living Under a Common Roof." Locally sourced clay and steel are used to minimize transport distances. Positioned beneath the bridge, the houses are shielded from extreme weather. A serving wall and double facade ensure cross-ventilation and natural cooling. The design prioritizes adaptability, affordability, and sustainability, dynamically responding to residents' needs with adjustable private and common spaces. Adaptable circulation connects vertical private rooms, and financial compensation is provided for extended private areas. This evolving design addresses Vietnam's housing crisis by activating underutilized spaces, such as the 750-meter-long Phu My Bridge. The traditional tube house, which is narrow yet long, has been adapted to create more vertical living space. The design revives communal and climate benefits, offering affordable housing near industrial zones. By emphasizing transition zones between indoor/outdoor and private/shared spaces, each unit includes two tube houses and shared vertical circulation. Public areas like playgrounds, shops, and green spaces are integrated to foster community and sustainability.
Highlighted Submissions
Project Title: Re-Bridge
Authors: Jiming Bai, Yuejun Han, Yinong Ge and Yifan Zhang, from the USA
Demographia’s 2023 survey highlights critical housing affordability issues in 81 global cities. Many of these cities feature underutilized spaces beneath elevated transportation systems, presenting a unique opportunity to create affordable housing while reconnecting divided communities. The Re-Bridge project aims to repurpose these under-bridge areas despite challenges such as limited natural light, noise, and air quality. Design solutions include elevating residential units, incorporating vertical greenery, and using perforated panels to enhance privacy and light. Public spaces and retail at ground level will further improve the urban environment. A prime candidate for this initiative is the under-bridge space near Brightline Miami Station, currently used for parking, which could be transformed to revitalize and reconnect downtown Miami.
Project Title: UNDERLINE
Authors: Jiansong Yuan and Xiaotong Ni from the USA
The UNDERLINE housing project reimagines urban living by transforming underutilized spaces beneath bridges into vibrant community hubs. The design integrates existing bridge structures with modern elements, creating a sustainable and welcoming environment for residents and the surrounding neighborhood. Chicago, with its numerous bridges and underused spaces, is an ideal location for UNDERLINE. The city’s extensive infrastructure presents a unique opportunity to address the pressing need for affordable housing. By reclaiming these neglected areas, UNDERLINE not only revitalizes urban landscapes but also fosters community engagement and economic development in underserved neighborhoods.
Project Title: Underbridge Homes
Authors: Anqi Wang, Hao Zhou, Yue Liang, Ruijing Sun from the USA
New York City, with its blend of historic architecture and modern technology, faces growing challenges due to its dense population and limited land availability. Many abandoned railways and spaces beneath bridges present a unique opportunity to repurpose these areas for affordable housing. This project aims to transform underutilized bridge spaces into modular homes for low-income residents, revitalizing neighborhoods and enhancing community connections. The proposed modular units—ranging from studios to two-bedroom apartments—are designed to fit seamlessly beneath bridges, using minimal space while addressing noise and safety concerns. These units will be connected by corridors and shared public spaces, including essential amenities such as fitness centers, laundry rooms, and plazas. The bridge deck above will remain part of the transportation network and feature innovative landscaping. Drawing inspiration from the arch structures of the bridges, the design integrates harmoniously with the existing framework, creating a dynamic and sustainable urban living environment.
Project Title: Living Synthesis
Authors: Yangtong Zhao, USA
Living-Synthesis aims to create adaptable, affordable housing beneath New York City's bridges, transforming underutilized spaces into vibrant, permanent communities. Unlike typical affordable housing projects, this initiative focuses on long-term livability rather than merely minimizing costs. Using the Manhattan Bridge as a prototype, Living-Synthesis envisions a hyper-dense, interconnected community spread across multiple bridge sites. The project features customizable, modular residential units that residents can expand based on their needs, along with public spaces, vertical farms, and other amenities. These adaptable elements foster a self-sustaining environment that addresses housing affordability while promoting community engagement. By integrating innovative solutions into existing infrastructure, Living-Synthesis not only provides permanent housing but also revitalizes urban spaces and enhances the quality of life for New Yorkers.
Buildner's competitions place a strong emphasis on housing and compact living in response to the climate and economic crises facing cities worldwide. Current ongoing events include the MICROHOME competition, which offers a €100,000 prize fund for innovative ideas related to small-scale living. Another event, the Denver Single Stair Housing Challenge—the 18th competition in Buildner's Affordable Housing Challenge series—aims to address the housing crisis in Colorado, USA. This challenge invites architects, designers, and urban planners from around the globe to reimagine the potential of Point Access Block housing, or single-stair housing, in the U.S. Participants are tasked with designing mid-rise buildings, up to six stories high, on underutilized lots in Denver.
