Policy — Allow Single Staircase Buildings
March 26, 2025
Building codes that seek to keep people safe, but that were created in a time of lesser fire suppression technologies, have created a two staircase requirement for most buildings. This makes small buildings expensive and difficult to build. We recommend eliminating the requirement while maintaining safety through modern building methods like pressurized stairwells, sprinkler systems, and fire rated doors and walls.
A Building in Seattle Constructed Using the Single-Stair Design Element, Credit: Sean Jursnick
This is the seventh entry in our ongoing Policy series. Pittsburgh is in the midst of a severe housing crisis, with many neighborhoods becoming increasingly out of reach for many families. While the causes for our housing problems today are many, the goal of Pro-Housing Pittsburgh is to advocate for each and every change that can lessen the extent of the crisis. Each entry in this series describes a specific Policy that can be undertaken by the local government to help with the housing crisis in Pittsburgh.
The Problem
In American cities that came up before the age of the automobile, nothing feels more familiar than a walkup apartment. Usually 4-6 stories, with a single shared staircase going up to each apartment, they are by far the most common apartment type that exists in the world. However, if you look at modern apartment construction in the US, you will notice they often seem to share a similar design: a single, long building following a central hallway with apartments splitting off on either side. These buildings can attract criticism for feeling bulky, tending to look alike, and for providing mainly small apartments. It turns out that this is not by accident, but rather stems from building codes which require that every apartment has two or more ways for exiting the building, thus requiring two stairways. These building codes seek to keep people safe but were created in a time of lesser fire suppression technologies and materials. As a result of the two staircase requirement, buildings are more expensive and difficult to build.
Recently, a movement has started to sweep across various cities and states to remove this requirement and let apartments be built with a single-staircase. We at Pro-Housing Pittsburgh support this, and like other proponents we believe that changing this policy would open up a wider variety of apartment options, particularly for family-sized units. It would also make small to midsize projects less expensive to build and encourage denser construction on smaller vacant lots. By bringing down construction costs and allowing builders to build where it may not previously have been feasible, we should see more available homes and lower rents citywide.
The Building Code Today
In Pittsburgh, and nearly every city across North America, the design and construction of our buildings are regulated by the International Building Code or IBC (the term ‘International’ here is a misnomer, it only applies to the US and Canada). The IBC covers everything from plumbing and fire safety to swimming pools and green construction. In the IBC there is a requirement that each unit in a multi-unit building above 2-3 stories provide multiple means of egress. This essentially means that from your front door, there needs to be more than one way to exit the building. When a building has more than one floor, this then necessitates the construction of more than one staircase. When a minimum of two staircases are required, it also implicitly requires a long hallway linking the two stairs. The only remaining choice is to either place rooms on one side or two sides of the hallway, but in practice the choice is always to place rooms on both sides in order to utilize the hallway as well as possible. This design is commonly referred to as a “double loaded” corridor, referring to the fact that apartments are built on either side of a shared hallway, creating a hotel-like appearance from inside.
