Fremont · Zoning · O-S
Fremont O-S zoning: height, setbacks and lot size
In Fremont's O-S zone, generally buildings can be up to 30 ft tall, the front setback is 50 ft and the minimum lot size is 40 acres, with the conditions listed below (Fremont code, read October 2026).
Key points
- Maximum building height: 30 ft (all other open space designations)
- Minimum front setback: 50 ft (10 acres and larger)
- Minimum side setback: 50 ft (10 acres and larger)
- Minimum rear setback: 50 ft (10 acres and larger)
- Minimum lot size: 40 acres (nonprime agricultural land under Agricultural Preserve Contract)
O-S (OPEN SPACE DISTRICT) is a zoning district in Fremont. Every value below was read from the Fremont Municipal Code and links to its section (read October 2026). State laws such as the ADU and SB 9 rules can allow more on a residential lot. General information, not legal advice — read the code text and check with the city before you build.
Development standards in O-S
The general rule for a typical lot in this zone. Zoning tables often attach notes, such as rules for corner lots, lots next to a residential zone, or new subdivisions only. Open “code text” under a value to see the table cell or sentence it was read from.
| Maximum building height | 30 ft Applies: all other open space designations § 18.55.020 · code textBuilding height1 shall not exceed 35 feet within the city park designation and 30 feet in all other open space designations, except as provided for in Section 18.170.020. |
|---|---|
| Minimum front setback | 50 ft Applies: 10 acres and larger § 18.55.030 · code textTable row “10 acres and larger | Front”, column “Yard least depth 1,2 (feet)”: 50 |
| Minimum side setback | 50 ft Applies: 10 acres and larger § 18.55.030 · code textTable row “10 acres and larger | Side”, column “Yard least depth 1,2 (feet)”: 50 |
| Minimum rear setback | 50 ft Applies: 10 acres and larger § 18.55.030 · code textTable row “10 acres and larger | Rear”, column “Yard least depth 1,2 (feet)”: 50 |
| Minimum lot size | 40 acres Applies: nonprime agricultural land under Agricultural Preserve Contract § 18.55.030 · code textTable row “Nonprime agricultural land 2”, column “Minimum Lot Area (acres)”: 40 |
When a different number applies
The code sets other values for particular lots, buildings or locations in O-S:
- Maximum building height: 35 ft — within the city park designation § 18.55.020
- Minimum lot size: 100 acres — nonprime agricultural land located above the toe of the hill line and annexed to the city after January 1, 2002, under Agricultural Preserve Contract § 18.55.030
- Minimum lot size: 1 acre — unconstrained land designated hill area open space on the general plan and not under Agricultural Preserve Contract § 18.55.030
- Minimum lot size: 4 acres — constrained land designated hill area open space on the general plan and not under Agricultural Preserve Contract § 18.55.030
- Minimum lot size: 20 acres — General, hill or hill face open space, no Agricultural Preserve Contract; hill areas may be smaller if clustered under a use permit § 18.55.030
Not on this page
We did not find a general stories, lot coverage, FAR, density limit for O-S in the zoning tables we read. The code may still set one elsewhere — check the Fremont Municipal Code.
Who this affects
Frequently asked questions
What is the maximum building height in Fremont's O-S zone?
30 ft (all other open space designations) — Fremont Municipal Code § 18.55.020.
What is the minimum front setback in Fremont's O-S zone?
50 ft (10 acres and larger) — Fremont Municipal Code § 18.55.030.
What is the minimum side setback in Fremont's O-S zone?
50 ft (10 acres and larger) — Fremont Municipal Code § 18.55.030.
What is the minimum rear setback in Fremont's O-S zone?
50 ft (10 acres and larger) — Fremont Municipal Code § 18.55.030.
What is the minimum lot size in Fremont's O-S zone?
40 acres (nonprime agricultural land under Agricultural Preserve Contract) — Fremont Municipal Code § 18.55.030.
General information, not legal advice.
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