Fairfax · Zoning · O-A
Fairfax O-A zoning: height, setbacks and lot size
In Fairfax's O-A zone, generally buildings can be up to 35 ft tall and the front setback is 6 ft, with the conditions listed below (Fairfax code, read October 2026).
Key points
- Maximum building height: 35 ft
- Minimum front setback: 6 ft (Building site slope not more than 10 percent; front and rear yards combined must be at least 25 feet.)
- Minimum side setback: 5 ft (Building site slope not more than 10 percent; two side yards combined must be at least 15 feet.)
- Minimum rear setback: 6 ft (Building site slope not more than 10 percent; front and rear yards combined must be at least 25 feet.)
O-A (OPEN AREA ZONE) is a zoning district in Fairfax. Every value below was read from the Fairfax 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-A
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 | 35 ft § 17.128.060 · code textHeight regulations in the O-A zone are as follows: Except as otherwise permitted by variance, no structure shall be higher than 35 feet above natural grade. |
|---|---|
| Minimum front setback | 6 ft Applies: Building site slope not more than 10 percent; front and rear yards combined must be at least 25 feet. § 17.128.070 · code text(1) A front and rear yard having a combined depth of not less than twenty-five feet but neither having a depth of less than six feet; |
| Minimum side setback | 5 ft Applies: Building site slope not more than 10 percent; two side yards combined must be at least 15 feet. § 17.128.070 · code text(2) Two side yards having a combined width of not less than 15 feet, but neither yard having a width of less than five feet. |
| Minimum rear setback | 6 ft Applies: Building site slope not more than 10 percent; front and rear yards combined must be at least 25 feet. § 17.128.070 · code text(1) A front and rear yard having a combined depth of not less than twenty-five feet but neither having a depth of less than six feet; |
When a different number applies
The code sets other values for particular lots, buildings or locations in O-A:
- Minimum rear setback: 12 ft — Building site slope more than 10 percent; front and rear yards combined must be at least 35 feet. § 17.128.070
Not on this page
We did not find a general stories, lot size, lot coverage, FAR, density limit for O-A in the zoning tables we read. The code may still set one elsewhere — check the Fairfax Municipal Code.
Other Fairfax zoning districts
Who this affects
Frequently asked questions
What is the maximum building height in Fairfax's O-A zone?
35 ft — Fairfax Municipal Code § 17.128.060.
What is the minimum front setback in Fairfax's O-A zone?
6 ft (building site slope not more than 10 percent; front and rear yards combined must be at least 25 feet) — Fairfax Municipal Code § 17.128.070.
What is the minimum side setback in Fairfax's O-A zone?
5 ft (building site slope not more than 10 percent; two side yards combined must be at least 15 feet) — Fairfax Municipal Code § 17.128.070.
What is the minimum rear setback in Fairfax's O-A zone?
6 ft (building site slope not more than 10 percent; front and rear yards combined must be at least 25 feet) — Fairfax Municipal Code § 17.128.070.
General information, not legal advice.
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