Costa Mesa · Zoning · I&R
Costa Mesa I&R zoning: height, setbacks and lot size
In Costa Mesa's I&R zone, generally buildings can be up to 4 stories, the front setback is 20 ft and the minimum lot size is 6,000 sq ft, with the conditions listed below (Costa Mesa code, read October 2026).
Key points
- Maximum number of stories: 4 stories (South of the I-405 Freeway; special purpose housing may be granted more height.)
- Minimum front setback: 20 ft
- Minimum side setback: 5 ft (Interior lot line; the planning commission may require more to protect adjacent land uses.)
- Minimum rear setback: 5 ft (Interior lot line; the planning commission may require more to protect adjacent land uses.)
- Minimum lot size: 6,000 sq ft
I&R is a zoning district in Costa Mesa. Every value below was read from the Costa Mesa 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 I&R
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 number of stories | 4 stories Applies: South of the I-405 Freeway; special purpose housing may be granted more height. § 13-66 · code textTable row “Maximum building height”, column “I&R and I&R-S”: Four stories south of the I-405 Freeway except that special purpose housing (e.g., affordable, elderly and student housing) may be granted additional building height. |
|---|---|
| Minimum front setback | 20 ft § 13-66 · code textTable row “Front”, column “I&R and I&R-S”: Twenty feet |
| Minimum side setback | 5 ft Applies: Interior lot line; the planning commission may require more to protect adjacent land uses. § 13-66 · code textTable row “Interior lot line”, column “I&R and I&R-S”: Five feet. Additional setback may be required by the planning commission if deemed necessary to protect adjacent land uses. |
| Minimum rear setback | 5 ft Applies: Interior lot line; the planning commission may require more to protect adjacent land uses. § 13-66 · code textTable row “Interior lot line”, column “I&R and I&R-S”: Five feet. Additional setback may be required by the planning commission if deemed necessary to protect adjacent land uses. |
| Minimum lot size | 6,000 sq ft § 13-66 · code textTable row “Minimum lot area”, column “I&R and I&R-S”: Six thousand square feet |
Uses in I&R
Uses the code's use tables allow in I&R, or allow with a permit. Each links to its page with the code section.
- Child care center — Needs a conditional use permit — see note
Not on this page
We did not find a general height, lot coverage, FAR, density limit for I&R in the zoning tables we read. The code may still set one elsewhere — check the Costa Mesa Municipal Code.
Other Costa Mesa zoning districts
Who this affects
Frequently asked questions
What is the maximum number of stories in Costa Mesa's I&R zone?
4 stories (south of the I-405 Freeway; special purpose housing may be granted more height) — Costa Mesa Municipal Code § 13-66.
What is the minimum front setback in Costa Mesa's I&R zone?
20 ft — Costa Mesa Municipal Code § 13-66.
What is the minimum side setback in Costa Mesa's I&R zone?
5 ft (interior lot line; the planning commission may require more to protect adjacent land uses) — Costa Mesa Municipal Code § 13-66.
What is the minimum rear setback in Costa Mesa's I&R zone?
5 ft (interior lot line; the planning commission may require more to protect adjacent land uses) — Costa Mesa Municipal Code § 13-66.
What is the minimum lot size in Costa Mesa's I&R zone?
6,000 sq ft — Costa Mesa Municipal Code § 13-66.
General information, not legal advice.
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