New fire codes can fix housing crisis
Now that zoning laws are changing across California to allow apartment buildings in more places, the next barrier to easing the state’s housing crisis is construction costs.
Bay Area construction costs are among the highest in the country, which means that even if housing is now legal to build in more places, it is uneconomical to do so.
One way to cut costs is to have more efficient floorplans. In a typical apartment building, circulation (hallways, stairs, and elevators) takes up around 12%-20% of each floor. In short, that means 12%-20% of your rent isn’t paying for the apartment, it’s paying for hallways.
Think about the typical new apartment building in California — it often takes up a whole block and is laid out like a hotel — long hallways with dozens of apartments on both sides. This building type is known as a “double-loaded corridor.”
In contrast, most apartment buildings around the world are “point access blocks.” Instead of a long hallway, there is a small lobby with just a few apartments opening onto it, sometimes just two per floor. In this layout, circulation is only 5%12% of each floor. Other benefits include apartments with windows facing more than one direction, allowing cross ventilation and providing more natural lighting.
Apartments in California are built with so much hallway space because in this state, and in most of North America, any apartment building with more than three floors is required to have two sets of stairs. The idea is that if one of the stairwells is blocked by fire, people can use the other stairwell.
However, when a hallway fills up with smoke, getting to either stairwell becomes difficult. Modern building code recognizes this danger and is written to engineer buildings to contain the fire and smoke to the room where it started. This includes mandatory sprinklers and firerated walls, doors and air ducts that keep flames and smoke from spreading.
Would a building that has both sprinklers and two stairs be safer than an identical one with sprinklers and one stair? Yes. However, when looking at the impact of mandated twostair buildings on the whole society, there are other factors.
First, the two-stair rule leads to larger buildings. A fire in a single-stair building may threaten a dozen apartments. A fire in a two-stair building threatens hundreds of apartments because smaller buildings are economically infeasible to build with two stairwells. The more apartments there are in a building, the greater the chance each year that there will be a fire somewhere in the building.
Second, modern fire codes only apply to new construction. Older buildings built before sprinkler requirements are not required to upgrade. When high construction costs limit the production of new buildings, more people are forced to live in old ones that lack modern safety features.
Given these tradeoffs, most of the world has decided that it’s safer to have modern singlestair buildings rather than giant double-stair buildings or continue using outdated housing with no sprinklers. While cities in the United States typically only allow three-floor singlestair buildings, building codes in other countries often allow five to 10 floors with a single stair.
Two major cities in the United States have gone in a similar direction as their international counterparts: New York and Seattle. New York allows small residential buildings up to six stories tall to be built with a single stairwell as long as each floor has an area of less than 2,000 square feet (roughly two to four apartments). New York’s code also bans wood construction.
Seattle’s single-stair building code allows up to six stories, with a limit of four apartments per floor. It also requires the hallways, stairs and elevators to either be open air or pressurized to keep smoke from spreading from an apartment into the hallway. Sprinklers and fire-resistive construction are also mandatory. This code would be the best model for California, as our construction methods and lot sizes are similar.
On Monday, Assembly Member Alex Lee, D-San Jose, introduced a bill, AB835, to study the benefits of single-stair residences and develop new standards for making them legal to build.
Through single-stair codes for mid-rise apartment buildings, we can have housing that is cheaper, safer, and better. California should look to our neighbors to the north and learn from them.