Austin, the southern city leading the charge for bringing down housing costs, just hit another milestone. The capital of the Lone Star State approved a resolution for five-story single-stair apartment buildings throughout the city earlier this month — a game changer for housing density and driving housing costs down, advocates say.
The city released a press release about the adoption of 2024 Technical Building Codes on April 10, saying the adoption is aimed at “improving safety, sustainability, and housing flexibility.”
The release also stated that the vote included approaching a “comprehensive set of local amendments tailored to support Austin’s unique environmental and housing goals.”
Austin has been hailed as a case study for urbanists and housing advocates alike due to its seemingly successful strategy of building more denser housing. Reports indicate that average rent in the city has fallen for the last year and a half — with some reports saying average rent is now $400 less than their record high. It’s a trend that single-stair advocates say the newly approved building code amendments can help further.
The Texas Donut
Parker Welch, a civil engineer and a board secretary for the nonprofit organization AURA, which is focused on all things urbanism in Austin, has been helping lead the effort for single-stair adoption for the last couple of years.
Strategies as simple as giving away shirts calling for single-stair adoption at hearings and meetings, Welch said, also helped the movement become more visible.
Single-stair buildings are not to be confused with simply removing all but one staircase in modern apartments that we see today, Welch emphasized. The building itself will have entirely different designs.
“It’s kind of like a whole different way of building the multifamily development, but it’s not a really strange one,” Welch said. “It’s one that we’ve all seen… especially if you lived in a foreign country or even just an older building in a place like New York.”
The single staircase forms the “core” of the building, with the units being built around it. The staircase, though commonly indoors, can be outdoors. Due to their design, they effectively get rid of hallways that make up “wasted space” in other building types, leaving more space for the actual units. The building can also come with an elevator, and in fact, many built above three stories have one.
With the buildings only needing one staircase, they can be built in more compact environments in an urban core and also save developers money on the construction of the building itself — which, in theory, would reduce the cost of housing for the building tenants.
“These buildings, you can really think of them as skinnier,” Welch said. “If you imagine a brownstone in New York or almost any apartment in Paris or Barcelona or Tokyo, they are much taller and skinner, and they definitely don’t look like those big hulking Texas Donuts [buildings].”
The Texas Donut is a nickname used to describe buildings that wrap around a parking deck in the center, common across Texas. The Texas Donut has been a viable option, especially for projects where underground parking would drive costs up; they aren’t exactly “skinny,” however, and because of this, are more difficult to embed into an urban fabric with smaller parcels of land available to build upon — an area where single-stair buildings, which are generally smaller, tend to thrive.
“It makes for horrible urbanism, very chunky urbanism, whereas a single-stair building, by necessity, is a smaller footprint building even though the units inside are larger,” said Chris Gannon, architect and committee chair for the American Institute of Architects Austin Housing and Affordability Committee and a member of the City of Austin’s Building and Fire Code Board of Appeals. “You can fit them on existing lots. A lot of times in older neighborhoods, lot sizes are going to be a lot smaller, so you can fit a small, neighborhood-sized apartment building. If you’re mandated to have two staircases and a corridor that connects them, there’s just no way.”
Quantity and quality
“It’s a way to increase not just the quantity of housing but quality as well,” Welch said. “What happens when we put the hallway in the middle of the building is that now, you have a bunch of units next to each other, and they have a unit on one side, a unit on the other side, a hallway on the third [front-facing] side, and the only side that’s left that can have a window and natural light coming in is that fourth wall to the outside of the building.”
This can lead to people needing to turn lights on during the day and limit the potential layouts of a unit since most people don’t like bedrooms with no windows.
Welch added corner units are an exception, having two walls that can have windows — but they aren’t the majority within a building of that type of build. With single-stair buildings, though, that isn’t the case.
“You can think of it like every unit is a corner unit, and you can have windows on multiple sides; it also means that you can put a more diverse mix of units, where you can have, say, three-bedroom units that a family might actually live in,” Welch said. “When you’re trying to find a three-bedroom unit, it’s like asking for a unicorn. They exist, but almost all of them are leased up, and you’re not going to find very many of them.”
With the benefit of multiple windows comes the possibility of a cross breeze, Welch added, which is a big plus for warmer summer months in places like Austin and Atlanta.
“There’s this question of ‘how do we urbanize our southern, post-war cities,'” Gannon said, noting that southern cities tend to be characterized by larger lot sizes, highways, and urban sprawl. “I think that single-stair is going to lead to wildly imaginative, really cool new building types. I think we’re on the verge of a new revolution in American housing that has to do with how we fix our auto-centric cities.”
The path forward may, in fact, be behind us, Gannon explained.
“As we rewind history, the way that we used to live was different. In fact, if we think about Boston, a major building type is the Boston Triple-Decker,” Gannon said. “Three units stacked up with one staircase… it was outlawed by the International Residential Code, so you had to build it under the International Building Code, which is a more expensive code. So it’s kind of been written out of the code for most American cities.”
The tallest buildings in the country are built under the International Building Code, along with strip malls, airports and other non-residential buildings. Hence, putting the triple-deckers into the same code as skyscrapers discouraged developers from building them. Additionally, single-family zoning — common across the U.S. — limited where they could be built.
“[They] were a major way for immigrants to reach the middle class and gain wealth by being able to buy one unit in a triple-decker, and as their family would grow they would maybe buy the second unit, and eventually the full three-unit building — and then as their kids got married or went off to other cities, they were able to lease those units to other folks and kind of age in place.”
And while they may not be as common as other types of homes nowadays, Gannon remarked, the important lesson to remember is that they did exist and helped shape cities — a role he believes single-stair buildings in Austin and elsewhere can fill.
The elephant in the room in terms of opposition to these buildings is safety. Is this just giving more leeway for developers to build cheaper housing while sacrificing the safety of tenants?
In the past, when single-stair buildings were more commonly built, other building safety codes didn’t exist, especially in low-income housing. Disasters eventually led to the introduction of a second staircase for increased safety measures.
“Now, we’re so far away from that. Our buildings are much sturdier, more hardened, and they come with sprinklers,” Gannon said. “We have compartmentalization to contain fires… there are egress [exit] distance requirements, so no one is more than 20 feet from their staircase… there are all these safety provisions that are built-in, and modern buildings are just so much safer.”
In other words, our advancements in safety are enough to warrant the mandating of second stairways for buildings under five stories.
Staying ahead of the curve
“We believe that the crisis is so deep and solidified by existing structures that it is always too soon to declare victory because you don’t know what’s going to happen next,” Welch said. “Tariffs sending up material costs, interest rates rising so it’s harder to get a loan to build a new building — you kind of have to keep preparing for what’s going to come next.”
Austin, Welch said, was not prepared for the growth it had experienced in recent years when it increasingly became a popular city for people, and that failure meant renters were fighting for the scarce housing that was unaffordable. It’s also part of the reason that Austin is building so much more housing today — intentional efforts to course-correct.
Part of the reason Austin has taken a lead on this front, too, is because of the way local councilmember elections were changed. In 2014, the city council elections were changed from at-large voting across the city to electing council members by its 10 districts, with only the mayor being decided citywide. This has allowed for more accountability and better representation for distinct areas of Austin.
In all, Welch and other advocates are happy to see bold steps from Austin — and hope that with their predicted successes, other cities will follow suit.
The building code amendments adopted by Austin will officially go into effect on July 10, 2025.
