You book a small hall for a family party and a laminated card by the door says the room holds a maximum of 74 people. Not 70, not 75 — 74. Or you are fitting out a studio and the plan checker asks you for the occupant load before she will look at anything else. Either way the same question comes up: where does that number actually come from, and who decides it?
California does not set a flat headcount. A room's capacity is worked out from its floor area, divided by a factor set for how the room is used — 200 square feet per person for residential space, 60 for a store, 20 for a classroom (Table 1004.5). Whatever the use, the count may never exceed one person per 7 square feet (§ 1004.5.1).
Key numbers
Each figure below is the floor area the code allows per person. A bigger number means fewer people in the same room.
| What the space is used for | Floor area per person | Where it comes from |
|---|---|---|
| Residential | 200 sq ft (gross) | Table 1004.5 |
| Classroom | 20 sq ft (net) | Table 1004.5 |
| Day care | 35 sq ft (net) | Table 1004.5 |
| Exercise room | 50 sq ft (gross) | Table 1004.5 |
| Mercantile — the code's word for retail | 60 sq ft (gross) | Table 1004.5 |
| Library reading room | 50 sq ft (net) | Table 1004.5 |
| Commercial kitchen | 200 sq ft (gross) | Table 1004.5 |
| Dormitory | 50 sq ft (gross) | Table 1004.5 |
| Stage or platform | 15 sq ft (net) | Table 1004.5 |
| Warehouse | 500 sq ft (gross) | Table 1004.5 |
| Absolute ceiling, any use | 7 sq ft | § 1004.5.1 |
How the number is worked out
The term the code uses is occupant load — the number of people a space is designed to hold. For a room without fixed seating, you take the floor area and divide by the factor for that use. A 1,200-square-foot classroom at 20 square feet per person works out to 60 people. The same room used as a retail floor, at 60 square feet per person, holds 20.
That is why the posted number is so specific, and why it changes when a tenant changes. Nothing about the walls moved; the use did.
One detail matters more than it looks. Each factor in the table is marked either net or gross, and the two are different measurements of the same room — the code defines them elsewhere, and the pack of sections behind this article does not include those definitions. Which one applies changes the answer, sometimes a lot. So treat the arithmetic above as how the method works, not as a number to put on a permit application. Your building department settles the measurement.
The ceiling nobody can raise
A designer may ask for a higher occupant load than the table produces — a room laid out efficiently, with enough exits, can legitimately hold more people than the default factor suggests. The code allows that increase, but it stops at a hard line:
the occupant load does not exceed one occupant per 7 square feet of occupiable floor space
Seven square feet is roughly the footprint of a person standing in a crowd. Below that, the room cannot empty fast enough in an emergency, and no design gets you past it.
The same section lets the building official require a diagram showing the aisles, seating or fixed equipment that justifies the higher number — and require that diagram to be posted. If you have ever seen a seating plan in a frame next to the capacity card, that is what it is.
Why the number matters: it decides your exits
Occupant load is not a bureaucratic formality. It is the input that decides how many ways out a space needs. Above a threshold that depends on the use, one door is no longer enough and a second exit is required (§ 1006.2.1).
That threshold is not one number. For several common commercial uses a single exit serves up to 49 people. For apartment-type occupancies it drops to 20, and for some residential and institutional categories to 10. For the highest-hazard spaces it falls to 3 people — and high hazard here means the manufacturing, processing or storage of materials that are a physical or health hazard in quantities above what the code otherwise permits (§ 203.6).
The practical consequence is that raising a room's capacity is rarely just paperwork. Push the occupant load past the threshold and you have bought yourself a second exit door, and everything that comes with it.
Occupancy is also a maintenance obligation, not a one-time approval. The fire code's general requirements govern the occupancy and maintenance of structures for precautions against fire, for the life of the building (§ 301.1).
Houses are handled by a different code
If you are asking about your own home, the occupant-load table is probably not your rulebook. Detached one- and two-family homes and townhouses of no more than three stories, plus the structures accessory to them, are covered by the California Residential Code rather than the building code chapters above (§ 1.1.3). That code sets minimum requirements for structural strength, exits, light and ventilation, sanitation and fire safety in dwellings, and it does not work by posting a maximum headcount on the wall.
What this does not answer
There is a second, very different question that gets searched with the same words: how many people are allowed to live in a rental. That is not what occupant load is. Occupant load is a life-safety figure about getting people out of a space; a limit on how many people may occupy a dwelling as their home is set by other law — local housing ordinances and the terms of a lease — and none of the sections behind this article address it. If that is your question, ask your city's housing or code-enforcement department rather than reading a number off the table above.
Building-code figures are a statewide floor. A city may adopt stricter local requirements, so confirm anything you plan to build against your own jurisdiction's amendments. You can browse more explainers on the GoCodebook blog.
Sources
- 2025 California Building Code § 1004.5 and Table 1004.5 — Occupant load, areas without fixed seating
- 2025 California Fire Code § 1006 — Numbers of exits and exit access doorways
- 2025 California Fire Code § 203.6 — High-hazard Group H
- 2025 California Fire Code § 301.1 — General requirements, scope
- 2025 California Residential Code § 1.1 — Title, purpose and scope
