You are replacing the counter and the flooring in your shop. The plans go in, and the plan checker comes back asking about the restroom at the back, the front entrance, and the parking stall out front — none of which you were touching. It reads like the city is holding your counter hostage over the whole building.
It is not arbitrary. In California, altering part of a building triggers a duty to provide an accessible path of travel to the area you altered — and that path expressly includes the primary entrance, the toilet and bathing facilities serving the area, drinking fountains, public telephones and signs (§ 11B-202.4). The cost of that path work is capped at 20 percent of the adjusted construction cost of your project (§ 11B-202.4, exception 8).
Key numbers
| The rule | What it says | Where it comes from |
|---|---|---|
| Path-of-travel cost cap | Limited to 20 percent of the adjusted construction cost | § 11B-202.4, exc. 8 |
| Above the valuation threshold | Full compliance not required where the agency finds unreasonable hardship | § 11B-202.4, exc. 8 |
| Prior-edition work | Reference back one code edition only, not cumulative | § 11B-202.4, exc. 2 |
| Additions | Must meet new construction requirements, plus the path of travel | § 11B-202.2 |
| Ceiling on the duty | An alteration cannot be held to a higher standard than new construction | § 11B-202.3.2 |
What counts as an alteration
The scoping rule is short and broad:
All areas of newly designed and newly constructed buildings and facilities and altered portions of existing buildings and facilities shall comply with these requirements.
That is § 11B-201.1. Where you alter an existing element or space, that element or space has to meet the applicable requirements — and it drags the path-of-travel section along with it (§ 11B-202.3).
Two limits keep this from running away, and they are worth knowing because plan checkers apply them:
- You cannot be held to a higher standard than new construction. Altering an existing element does not impose an accessibility requirement greater than what a new building would face (§ 11B-202.3.2).
- You cannot go backwards. An alteration that decreases accessibility below the new-construction requirements in effect at the time is prohibited outright (§ 11B-202.3.1).
There is also a rule that catches piecemeal work. If you alter single elements and those alterations, considered together, amount to altering a room or space, then the entire room or space has to be made accessible (§ 11B-202.3.3). Splitting one remodel into four small permits does not avoid the obligation.
The 20 percent cap, and what it actually caps
This is the number everyone has heard and most people state slightly wrong. It does not cap your project. It caps the path-of-travel work.
Where the adjusted construction cost is at or below the current valuation threshold, the cost of complying with the path-of-travel section is limited to 20 percent of the adjusted construction cost of the alteration, structural repair or addition. If full compliance would cost more than that, you provide compliance to the greatest extent possible without exceeding 20 percent (§ 11B-202.4, exception 8).
Where the adjusted construction cost is above that threshold and the enforcing agency determines that full compliance is an unreasonable hardship, full compliance is not required — you provide equivalent facilitation or comply to the greatest extent possible.
Note what the code does not hand you here: a dollar figure. Both "adjusted construction cost" and "valuation threshold" are defined terms, and the threshold is a moving number rather than something printed in this section. Ask your building department what the current threshold is before you budget around it.
Five alterations that do not drag the path of travel with them
The code names specific small jobs and limits them to their own scope of work (§ 11B-202.4, exception 3):
- Altering one building entrance.
- Altering one existing toilet facility.
- Altering existing elevators.
- Altering existing steps.
- Altering existing handrails.
Do one of those and you are not obliged to build out the whole path of travel. Alterations undertaken solely for barrier removal under the federal Americans with Disabilities Act are treated the same way.
There is one more relief valve people miss. If a path-of-travel element — the entrance, the restroom serving the area, the drinking fountain, the phone, the signs — was already built or altered to comply with the immediately preceding edition of the California Building Code, you do not have to retrofit it for the incremental changes in the current edition just because you altered an area it serves (§ 11B-202.4, exception 2). The code adds a warning in a note: that reference goes back one edition only and is not cumulative to older editions.
When compliance is technically infeasible
Sometimes the building fights back — a structural wall, a floor level that cannot move. Where the enforcing authority determines that compliance is technically infeasible, the alteration provides equivalent facilitation or complies to the maximum extent feasible (§ 11B-202.3, exception 2).
This is not a self-serve exemption. The code requires that the details of the technically-infeasible finding be recorded and entered into the files of the enforcing agency. If your designer is relying on infeasibility, there should be a written finding in the city's file, not just a note on the plans.
Spaces the requirements never reach
Chapter 11B also exempts categories of space outright, whatever you are doing to them (§ 11B-203): construction sites and their scaffolding and trailers; areas raised for security or life safety such as guard towers and lifeguard stands; limited-access spaces reached only by ladders, catwalks or crawl spaces; machinery spaces like elevator pits, mechanical and electrical rooms and transformer vaults; and single-occupant structures such as toll booths reached only by tunnel.
Residential dwelling units are handled separately. Units not required to be accessible under the code are not subject to the alterations section (§ 11B-202.3, exception 3), and residential path-of-travel questions route to a different section of the chapter.
What this page does not cover
This is Chapter 11B of the 2025 California Building Code, which governs public buildings, public accommodations, commercial buildings and public housing. It is a state floor; a city may enforce more.
Two things you will not find above: the current dollar valuation threshold, which is a defined term that changes and is not stated in this section, and the federal ADA obligations that run in parallel with the state code. Meeting Chapter 11B is not automatically the same as satisfying federal law, and this page does not address the federal side.
