Single Stair Reform and Housing Affordability

Key Takeaways

• Dual stair codes increase construction costs.
• Single stair designs free floor space.
• Fire safety comparable to dual stair buildings.
• Reform can boost housing supply and affordability.
• Advocates push policy changes nationwide.

Pulse Analysis

The United States’ building codes still require two independent exit stairways for every multifamily unit, a rule inherited from mid‑century fire‑safety concerns. While well‑intentioned, the dual‑stair mandate adds roughly 10‑15 percent to construction budgets, forces larger core footprints, and drives up rent for end users. In contrast, European cities routinely approve single‑stair towers, achieving tighter floor plates and lower per‑unit costs. As housing affordability tightens in major metros, developers and policymakers are scrutinizing this legacy requirement as a hidden cost driver.

Critics claim that a single stairway compromises fire safety, yet recent fire‑engineering studies show no statistically significant increase in evacuation times for well‑designed single‑stair towers. Proponents point to improved natural ventilation, larger daylight apertures, and more adaptable floor plans that can accommodate mixed‑use or community spaces. By eliminating redundant stair cores, developers gain up to 20 percent more rentable area, translating into lower unit prices without sacrificing egress standards. Cities that have piloted the reform, such as Seattle, report comparable safety outcomes and faster permitting cycles.

The single‑stair movement is now part of a broader reform agenda that includes ending single‑family zoning, reducing parking minimums, and encouraging district‑scale density. Advocacy groups led by Mike Eliason and Steven Smith have leveraged New York Times coverage and city‑level pilot projects to build political momentum. If municipalities adopt the reform, analysts estimate a potential 5‑10 percent reduction in construction costs, unlocking thousands of new affordable units over the next decade. The shift promises not only cheaper housing but also more varied, human‑scaled urban environments.