Building the lifelong neighborhood: Single-stair apartments in Texas
One promising pro-housing win of the 89th Legislature would open the door for a unique housing typology: the single-stair building. These small-scale, multi-family buildings feature a modest number of units per floor served by a single stairwell. They serve to increase the diversity of the state’s housing stock and offer an additional option for housing families within their existing communities.
While widely used in the rest of the world, they have been largely absent from the American landscape (though cities and states are catching on to their potential as a missing middle housing solution) due to limitations embedded in the International Building Code (IBC), a model building code used by most Texas municipalities.
Senate Bill 2835, authored by state Sen. Nathan Johnson, D-Dallas, and sponsored by state Rep. James Talarico, D-Austin, establishes a state-level regulatory framework that outlines safety standards specific to single-stair buildings. This gives Texas cities the ability to incorporate these standards into their own development codes regardless of their usage of the IBC, reducing administrative red tape and accelerating housing development.
The case for single-stair buildings is strong.
They are inherently more land-efficient and cost-effective than the “double loaded corridor” apartment buildings that are built now. Research from the Pew Charitable Trusts indicates that the second stairwell and connecting hallway necessary for a double loaded corridor building can add 6%–13% to construction costs. By eliminating these requirements, single-stair buildings can utilize up to 95% of the floor plate for living space, a significant improvement in design efficiency.
Their compact footprint also means they can be built on smaller urban parcels, adding housing to neighborhoods on plots of land that could not otherwise accommodate multifamily buildings. Under SB 2835, these buildings are capped at six floors and 24 units, preserving a neighborhood-friendly scale.
Beyond affordability, single-stair buildings offer design flexibility that supports the diverse needs of Texans. With windows on multiple sides of each unit, these apartments can accommodate more bedrooms and natural light, making them ideal for families. At the same time, their modest size and lower maintenance requirements make them attractive to older adults looking to downsize without leaving their neighborhood.
Double Loaded Corridor Floor Plan
Single-Stair Floor Plan
Graphics courtesy: Larch Lab
What do single-stair buildings look like?
Because of their limited use in the U.S., we can turn to proposed single-stair buildings like the building below, a winner of a single-stair architectural design competition in Denver:
Photo courtesy: Buildner
We can also look to places like Paris, where this six-unit social housing building shows how well a single-stair apartment can fit into the existing urban fabric.
Photo Courtesy: Metalocus
While single-stair buildings are a global standard, adopting them in Texas represents a step forward in housing dynamism. Just as Texas has embraced innovation in energy, technology and infrastructure, SB 2835 signals a willingness to bring that same spirit to housing — prioritizing both efficiency and livability.
By expanding the toolkit for city planners and developers, this legislation lays the groundwork for a more inclusive and sustainable housing future — one where every Texan can find a place to call home in a neighborhood that works for every stage of life.