The Future of Urban Architecture: Single-Stair Design and Its Impact

An architect’s office may not typically be a draw for tourists, but the Schemata Workshop office building, constructed in 2016 just east of downtown Seattle, has become an unexpected attraction. Its significance lies not only in its innovative design but also in its role within the Capitol Hill Urban Cohousing (CHUC) project, a rare contemporary example of single-stair architecture. This building type is garnering attention nationwide and even internationally, driven by a blend of innovative design, community engagement, and ongoing advocacy for code reform.

Understanding Single-Stair Architecture

Single-stair architecture refers to buildings that rise above four stories and operate with a single means of egress, meaning they feature only one stairway. Such design poses unique challenges, particularly in the United States, where zoning codes and fire safety regulations have made single-stair construction the exception rather than the rule. Estimates suggest that single-stair buildings are practically unfeasible across approximately 97% of the country due to stringent safety regulations.

Capitol Hill Urban Cohousing, which includes ground-floor office spaces and four stories of residential units, stands as a beacon of possibility in a landscape starved for affordable, high-density housing. Co-founder Mike Mariano notes the increasing interest, stating, “I do a monthly tour with legislators and building officials because there’s been so much interest.” This project’s innovative spirit ignites discussions on potential legislative reforms to ease the path for similar developments.

A Movement Gaining Momentum

The campaign for legalizing single-stair buildings accelerated significantly in 2021, propelled by a growing discourse on social media and a burgeoning interest among architects and advocates in building codes. Events like the last year’s AIA Conference on Architecture featured panels discussing single-stair design, while international design competitions sparked further creativity in the field. According to the Single-Stair Tracker, reform initiatives have emerged in 21 states and cities across North America, demonstrating a seismic shift in how architectural norms are being perceived.

There are ongoing reform efforts in Canada, where proposals have been laid out to alter national building codes to allow for single-stair residences up to six stories tall, with British Columbia having made strides in this direction as recently as August 2023.

Grassroots Advocacy

As the architectural landscape evolves, grassroots support for single-stair reform highlights a cultural clash in the building code community. Stephen Smith, executive director of the Center for Building in North America, insists that the YIMBY (Yes In My Backyard) movement’s growing interest in codes is compelling. He notes, “This is something the building code world often does not see.” The marriage of community advocacy and building design is becoming more pronounced, emphasizing the importance of integrating policy reform into the broader discussion of housing solutions.

Tackling Safety Concerns

The potential of single-stair architecture transcends mere aesthetic appeal. It is deeply connected to pressing issues such as housing affordability and sustainability. Architect Mike Eliason, an advocate for single-stair design, argues that ongoing objections from fire and code officials spotlight the need for democratizing discussions around building regulations. “If we want more high-quality spaces, these conversations need to happen more often,” Eliason stresses.

Historically, the International Building Code has insisted on multiple staircases for buildings over three stories. These codes emerged in response to urban safety crises in the late 19th and early 20th centuries. The result? Standard constructions that often yield larger, less efficient apartments with double-loaded corridors—ultimately hindering the potential for innovative living spaces.

Reimagining Urban Living

Single-stair projects, commonly known as point-access blocks, are established globally but remain under-utilized in North America—only a handful of jurisdictions permit them, including Seattle, New York City, and Honolulu. The reform initiative seeks to broaden this scope, ideally leading to an increase in housing density and variety while lowering construction costs.

Advocates like Conrad Speckert highlight the affordability benefits inherent in single-stair design. Research indicates that these structures can reduce the construction cost of apartments by 6% to 13%, freeing up funds that can be put to better use, such as implementing an elevator for individuals with disabilities. The increase in usable square footage can foster improved natural lighting and airflow within units, enhancing the living experience.

Political Shifts

Support for these reforms is gaining traction at the political level. Austin Councilmember José "Chito" Vela is advocating vigorously for the single-stair resolution, which recently passed. He argues that such reforms can improve affordability and accessibility to housing. Despite potential pushback from fire departments, Vela is optimistic that the pro-housing sentiment within the current council will ultimately prevail.

Most single-stair efforts are currently in the study stage, assessing how these projects affect fire safety and code compliance. With further studies wrapping up by 2026, advocates hope to compel lawmakers to embrace informed opinion over legislative hesitation.

The Future of Urban Housing

The National Fire Protection Association (NFPA) has recently felt pressure from this grassroots advocacy, holding symposiums to explore the single-stair concept. Although some fire officials remain skeptical, there is an unprecedented urgency to reevaluate the existing norms governing building safety. Recent data indicates a remarkably low correlation between single-stair buildings and fire incidents, challenging the long-held assumptions about the risks involved.

Drawing parallels to the movement for legalizing mass timber in the U.S.—which also required substantial code reform—the ongoing evolution of single-stair regulations raises the prospect of unlocking innovative designs for urban housing.

As code reforms take shape and community support grows, single-stair architecture holds the potential to transform urban landscapes across North America, leading to more affordable, efficient, and engaging living spaces.

Conclusion: A Call to Action

In the face of escalating housing crises, single-stair architecture embodies a refreshing and radical inquiry into how we can design spaces that prioritize community and sustainability. The call for reform is not merely a quest for architectural innovation; it is a movement towards democratizing our urban environments.

As more jurisdictions explore the possibilities, advocates will need to remain vigilant, pushing for data-driven policies that facilitate better housing solutions while ensuring safety and accessibility for all. Through collaboration and advocacy, single-stair projects may serve as a key to unraveling the complexities of contemporary urban living.

Patrick Sisson is a Chicago expat now residing in Los Angeles, where he covers design, policy, and the trends shaping our cities.