Stair Falls and Building Code Violations

Stairs are covered by detailed building rules: how high each step is, how deep each tread is, where handrails go and how high they sit. When a stair breaks one of those rules and someone falls, the violation can become powerful evidence. That is part of the claims described on our dangerous conditions of property page. The same rules apply to the falls covered on our slip, trip and fall injuries page.

California calls this negligence per se. It is not a separate claim. A decision the Judicial Council cites under CACI 418 describes it as an evidentiary presumption that affects the standard of care in a negligence case. This guide explains how the presumption works, which code applies to a given stair, and how owners answer it.

How does a code violation become evidence, step by step?

Identify the defect. Uneven step heights, a missing or loose handrail, a handrail at the wrong height, a broken tread or a missing guard.
Find the rule that applied. Often a building standard in Title 24 of the California Code of Regulations, the edition in force when the stair was built or altered, plus any local amendment. For rentals, the habitability and housing standards also apply.
Measure and document. Each step, each handrail and the lighting, before anything is changed.
The judge decides whether the rule sets the standard. Whether the injury was the kind the rule was meant to prevent, and whether you were in the protected class, are decided by the trial court as a matter of law, according to a decision cited under CACI 418.
The jury decides violation and cause. If you prove the owner violated the rule and that the violation was a substantial factor in your harm, the jury must find negligence unless the violation was excused (CACI 418).
The owner may try to rebut. The presumption is overcome if the owner shows it did what a person of ordinary prudence who wanted to comply with the law would have done (Evidence Code 669(b)(1); CACI 420).
Ordinary negligence remains available. If the presumption does not apply, you can still prove the owner failed to use reasonable care (CACI 418, Directions for Use; CACI 1001).

What exactly has to be shown?

Element of Evidence Code 669(a)	Who decides	In a stair case
The owner violated a statute, ordinance or regulation of a public entity	Jury	Measurements compared with the building standard in force, or with a housing statute such as Civil Code 1941.1
The violation proximately caused the injury	Jury	Showing that the uneven step or missing handrail, and not something else, led to the fall
The injury was the kind of occurrence the rule was designed to prevent	Judge	Stair and handrail rules address falls on stairs
You were in the class of people the rule protects	Judge	People using the stair, such as tenants, customers and visitors

Which building code applies to my stairs?

California's building rules are the California Building Standards Code, Title 24 of the California Code of Regulations, published by the California Building Standards Commission. The Commission's codes page lists Part 2, the California Building Code, and Part 2.5, the California Residential Code, along with the other parts. Those standards apply to all occupancies throughout the state (Health and Safety Code 18938).

The code is republished every three years, and the edition matters. The Commission lists the 2019 edition as effective January 1, 2020, the 2022 edition as effective January 1, 2023, and the 2025 edition as effective January 1, 2026, through December 31, 2028. A stair built in 2015 was built under an older edition than one built last year. Cities and counties can also adopt more restrictive building standards that are reasonably necessary because of local climatic, geological or topographical conditions (Health and Safety Code 18941.5), and the Commission's site keeps a page of local amendment ordinances.

Older buildings are not always held to today's numbers. California's list of conditions that make a building substandard, for example, exempts exit facilities that conformed with the law when the building was built and have been adequately maintained (Health and Safety Code 17920.3). Maintenance is a different matter: a rental unit is untenantable if it substantially lacks floors, stairways and railings "maintained in good repair" (Civil Code 1941.1), with no exception for age.

Where do handrail and step rules come from in Sonoma County?

Permit Sonoma, the County of Sonoma's permit office, publishes a residential handrail handout (BPC-001, version dated February 5, 2020) based on Chapter 10 of the California Building Code and section R311.7 of the California Residential Code. Among other points, it says:

Stairways must have handrails on each side, with exceptions such as stairs within a dwelling unit, which may have a handrail on one side only.
In single-family (group R-3) occupancies, a flight with fewer than four risers does not require a handrail.
Handrail height is measured from the stair tread nosing and must be uniform, not less than 34 inches and not more than 38 inches.
Handrails must be continuous for the full length of the stairway, with listed exceptions, and must leave 1 1/2 inches of clear space from the wall.

The handout is a summary dated 2020. The edition in force when the stair was built or altered is what a case is measured against, so the code text for that edition, not a handout, is what an expert compares. For outdoor stairs and balconies on apartment buildings, there is a separate state inspection law; see who is responsible when an apartment balcony or stair collapses.

Does a violation make the owner automatically liable?

No. Three limits apply. First, the court has to accept the rule as the standard of care. A decision cited under CACI 418 notes that courts have applied negligence per se to building code violations "only in limited situations." Second, you still must prove causation. A missing handrail matters if you reached for a rail that was not there; it may matter less if you were carrying a box with both hands. Third, the owner can rebut the presumption by proof that it acted as a reasonably prudent person who wanted to comply with the law would have acted (Evidence Code 669(b)(1)), or show another excuse listed in CACI 420.

The reverse is also true: meeting the code does not prove the owner was careful. A decision cited under CACI 418 says compliance with the law does not prove the absence of negligence, and one cited under CACI 1001 says compliance with safety regulations is relevant but not decisive when other circumstances call for more care. A worn, slick tread can be unsafe on a stair whose dimensions are perfect. In that case the claim rests on the basic premises rules (CACI 1001 and 1003) and on proof that the owner knew or should have known about the problem; see how to prove the owner knew about the hazard.

What if the owner fixed the stairs after my fall?

A repair or safety measure taken after an accident cannot be used to prove negligence in connection with that accident (Evidence Code 1151). That rule encourages owners to make repairs, but it means the evidence of how the stair looked and measured before the fix has to come from your side: photographs, measurements and witnesses from the days right after the fall.

What changes the answer?

The stair is in a rental building. A landlord must keep floors, stairways and railings in good repair (Civil Code 1941.1), and must take reasonable precautions against unsafe conditions in areas it controls, such as common stairs (CACI 1006). A decision cited under CACI 1006 lists a violated safety law among the situations where a landlord can be responsible.

The stair is on public property. A city or county is liable only for a dangerous condition it created or had notice of (Government Code 835), and a written claim is due within six months (Government Code 911.2). See what makes public property legally dangerous.

You fell at work. A decision cited under CACI 418 says Cal/OSHA provisions may be admitted to establish a standard of care in negligence cases, including claims against third parties. Read whether a Cal/OSHA citation helps an injury case.

You fell at a friend's house. Handrail rules differ for single-family homes, and a guest's claim has its own questions; see a fall at a friend's or relative's home.

The defect was a small lip, not a stair. A minor height difference may be found trivial as a matter of law (Government Code 830.2). Read what a trivial defect is.

The owner says the step was easy to see. Obviousness can remove a duty to warn, but not always the duty to fix a hazard people must use (CACI 1004); see whether you can recover when a hazard was obvious.

What could this look like? An example

For example, imagine a man leaving a dentist's office on the second floor of a small commercial building in Santa Rosa. The outdoor stair has a handrail on one side only, and the first step down is noticeably shorter than the others. He misjudges it, reaches to his right for a rail that is not there, and falls, injuring his shoulder and hip. That evening his wife photographs every step with a tape measure and the missing rail from both ends. A week later the building's manager installs a second handrail.

Under Evidence Code 1151, the new handrail cannot be used to prove the owner was negligent, but the photos and measurements show how the stair was. An expert compares them with the code edition in force when the stair was built or last altered. If the court accepts the standard, and the jury finds a violation that was a substantial factor in the fall, negligence is presumed (CACI 418) unless the owner proves an excuse (CACI 420). If the presumption does not apply, he can still argue the owner failed to use reasonable care (CACI 1001). This example is made up to show how the rules fit together; it says nothing about any real case.

What mistakes do people make in stair fall cases?

Measuring one step instead of every riser and tread on the flight, when the problem may be the difference between them.
Assuming today's code applies to a stair built years ago.
Letting a repair happen before the stair is photographed and measured.
Relying on the violation alone, without explaining how it caused this fall.
Overlooking the six-month claim when the building belongs to a city, county, school district or the State.

What should I do this week?

Photograph every step and handrail from both ends of the stair, with a tape measure in the frame.
Record the height of each riser, the depth of each tread and the handrail height measured from the step's front edge.
Note the lighting, anything on the steps and what you were carrying.
Keep your shoes and collect witness names.
Ask the owner or manager in writing to keep its maintenance and repair records and any video.
Get medical care and keep every record. If you hit your head, see how a brain injury is proven and valued, which covers falls too.
For a fall in Santa Rosa, our Santa Rosa page lists the local courts and claim offices.

Frequently asked questions

Is "negligence per se" a separate claim?

No. A decision cited under CACI 418 explains that it is not a separate cause of action, but an evidentiary presumption within a negligence claim.

Who decides whether a building code applies to my fall?

The judge decides whether the rule was meant to prevent this kind of injury and to protect people like you. The jury decides whether the rule was violated and whether the violation caused the harm.

The stair met code. Do I still have a claim?

Possibly. Compliance does not prove the owner was careful, and an unsafe condition can be proven under the general premises rules (CACI 1001 and 1003).

What excuses can an owner raise?

CACI 420 lists situations such as being unable to comply despite reasonable care, an emergency the owner did not cause, or compliance creating a greater risk. The owner carries the burden of proving the excuse.

Where can I read the building code?

The Building Standards Commission's codes page links to each part of Title 24 on its publisher's website, by edition. Use the edition in force when the stair was built or altered.

How long do I have to bring a claim?

Generally two years for a lawsuit against a private owner (Code of Civil Procedure 335.1) and six months for a written claim against a public entity. See California personal injury deadlines.

If you fell on a stair that may not have met the building code, contact Young Law Group today at (707) 343-0556 or through our contact page for a free consultation.

Can a building code violation prove my stair fall case in California?