{"id":186597,"date":"2026-01-23T13:05:52","date_gmt":"2026-01-23T20:05:52","guid":{"rendered":"https:\/\/www.biggerpockets.com\/blog\/?p=186597"},"modified":"2026-01-23T13:05:55","modified_gmt":"2026-01-23T20:05:55","slug":"california-staircase-building-code-changes-could-shift-the-multifamily-market","status":"publish","type":"post","link":"https:\/\/www.biggerpockets.com\/blog\/california-staircase-building-code-changes-could-shift-the-multifamily-market","title":{"rendered":"Rule Changes From AB 835 in California Could Shift the Multifamily Market in Big Ways"},"content":{"rendered":"\n

A stairway to heaven? Maybe. Higher <\/span>cash flow<\/span><\/a> for California landlords might be as simple as changing the number of enclosed staircases required in small <\/span>multifamily<\/span><\/a> buildings. <\/span><\/p>\n\n\n\n

That\u2019s the debate surrounding Assembly Bill 835. California\u2019s fire marshal is finalizing a report to comply with the bill and potentially reshape real estate investment across the state.<\/span><\/p>\n\n\n\n

Why Staircase Rules Matter to Small Landlords<\/span><\/h2>\n\n\n\n

Under today\u2019s International Building Code, which <\/span>is followed<\/span> in some capacity by most U.S. jurisdictions, buildings above three units must include at least two enclosed staircases, which shape the core of any apartment building. Assembly Bill 835 seeks to allow single-stair multifamily buildings with more than three units.<\/span><\/p>\n\n\n\n

The proposed ruling is by no means unique in America. Many jurisdictions, including Seattle and New York, allow single-family staircase buildings (up to six units). It is, however, a financial game-changer for small landlords, as <\/span>California YIMBY’s website<\/span><\/a> explains, reducing construction costs, creating more livable square footage, and allowing apartment buildings to <\/span>be constructed<\/span> on smaller, narrower, and oddly shaped lots. More apartments equal more cash flow.<\/span><\/p>\n\n\n\n

AB 835\u2019s author, Assemblymember Alex Lee, sees the bill as opening more sites rather than a dramatic rewrite of the code. Lee told<\/span> Mitpitasbeat<\/span><\/a>:<\/span><\/p>\n\n\n\n

\u201cI see AB 835 as a first step to revising California\u2019s building code on apartment staircases. If California were to permit single?staircase apartments above three stories, we could unlock previously undevelopable properties and create more high-density housing. Single?stair apartments also allow for more efficient use of building spaces, along with a greater variety of housing units.\u201d <\/span><\/em><\/p>\n\n\n\n

In practical terms, eliminating an extra staircase could create more usable exterior space, provide sorely needed extra parking, and facilitate higher rents and lower tenant turnover.<\/span><\/p>\n\n\n\n

The Opposition<\/span><\/h2>\n\n\n\n

The <\/span>Pew Charitable Trusts<\/span><\/a> estimates that single-stair four-to-six-unit buildings with relatively small floor plans cost roughly 6% to 13% less to build than comparable dual-stair designs, partly because they sit on narrower lots and use simpler cores. In addition, Pew states that safety <\/span>is not compromised<\/span> by eliminating the second staircase.<\/span><\/p>\n\n\n\n

National Fire Protection Association president Jim Pauley<\/span><\/a> stated, however, that safety records could not <\/span>be viewed<\/span> uniformly, saying, \u201cWhile the report celebrates the outcome of modern safety codes, <\/span>it could also be used<\/span> to open the door wider to bypassing the very process that developed them,\u201d pointing out that well-funded fire departments in New York and Seattle, which both allow a single exit staircase in buildings up to four stories under their respective codes, allow for much faster response times than elsewhere in the country.<\/span><\/p>\n\n\n\n

Fire unions have taken a harder line. The<\/span> International Association of Fire Fighters<\/span><\/a> (IAFF) has launched campaigns in various U.S. states and cities, including Los Angeles and Connecticut, arguing that single exit designs \u201cjeopardize escape routes and complicate firefighter response.\u201d In short, they claim affordability should not come before safety.<\/span><\/p>\n\n\n\n

\u201cWe all want to see more affordable housing built, but not at the expense of people\u2019s lives,\u201d General President Edward Kelly said on the IAFF website. \u201cOne stairwell means one way in and one way out. When firefighters are going up <\/span>and<\/span> families are trying to get down, that\u2019s a recipe for disaster.\u201d<\/span><\/p>\n\n\n\n

His sentiments <\/span>were echoed<\/span> by IAFF General Secretary-Treasurer Frank L\u00edma, who stated: <\/span><\/p>\n\n\n\n

\u201cThe removal of a second stairway as an emergency exit\u2014a critical life safety feature\u2014is not an acceptable trade-off for additional housing. That\u2019s the bottom line. The proponents of this \u2018only one way out\u2019 design <\/span>have an overreliance<\/span> on fire alarms and sprinklers to perform without fail. And that\u2019s a big gamble on public safety.\u201d  <\/span><\/em><\/p>\n\n\n\n

More Tech, Building Codes, and Safer Units<\/span><\/h2>\n\n\n\n

Advocates of single-staircase multifamily buildings point to increased safety standards and building codes, which have resulted in fewer fires. \u201cNew fire safety standards in our building code have made it so new buildings are much safer overall,\u201d Los Angeles council member<\/span> Nithya Raman<\/span><\/a> said in support of considering the change.<\/span><\/p>\n\n\n\n

As with many issues, the case for building code reform has<\/span> ultimately become political:<\/span><\/a> Advocates of an outright gas stove ban\u2014often the cause of <\/span>fires in<\/span> apartment <\/span>buildings<\/span>\u2014in favor of electrification have come up against the oil and gas industry, supported by the Trump administration.<\/span><\/p>\n\n\n\n

Other States Are Following Suit<\/span><\/h2>\n\n\n\n

The single-staircase argument is <\/span>being adopted<\/span> elsewhere. Colorado, Pennsylvania, Rhode Island, Minnesota, Oregon, Virginia, and Washington state have already adopted some form of single-staircase allowance for buildings over three stories, with some limitations tied to building size, according to Pew.<\/span><\/p>\n\n\n\n

The Push for Greater Housing Supply<\/span><\/h2>\n\n\n\n

The 2027 edition of the<\/span> International Building Code<\/span><\/a> is expected<\/span> to <\/span>ratify the<\/span> single staircase for apartments up to four stories, <\/span>under certain<\/span> defined limits, according to<\/span> Boston Indicators<\/span><\/a> and other sources.<\/span> The pressure to increase housing supply and staunch the affordability crisis by expanding the number of permissible units in small multifamily buildings has been a central argument for<\/span> zoning reform advocates<\/span><\/a>, keen to end single-family-zoned neighborhoods.<\/span><\/p>\n\n\n\n

As Single-Family Stalls, Multifamily Housing Takes on More Importance<\/span><\/h2>\n\n\n\n

Single-family housing starts hit an 11-month <\/span>low in mid-2025<\/span><\/a> amid higher borrowing and construction costs, underscoring the importance of maximizing multifamily housing. Conversely, multifamily starts soared 30.6% in June compared with the previous year, with all regions except the Midwest reporting stronger multifamily gains, according to <\/span>KPMG Economics<\/span><\/a>, which summarized National Association of Home Builders data.<\/span><\/p>\n\n\n\n

Final Thoughts: Practical Strategies for Landlords to Increase Cash Flow in Small Multifamily Buildings<\/span><\/h2>\n\n\n\n

Even if building code reform is successful in advocating for single staircases in small multifamily buildings, retrofitting apartment buildings accordingly is usually far more expensive than it\u2019s worth. <\/span><\/p>\n\n\n\n

However, there are more practical ways to increase cash flow with your existing multifamily units. These include:<\/span><\/p>\n\n\n\n