Portola Valley · Zoning · R-MF-23
Portola Valley R-MF-23 zoning: height, setbacks and lot size
In Portola Valley's R-MF-23 zone, generally buildings can be up to 38 ft (3 stories) tall and the front setback is 50 ft, with the conditions listed below (Portola Valley code, read October 2026).
Key points
- Maximum building height: 38 ft (Principal Structure)
- Maximum number of stories: 3 stories (Principal Structure)
- Minimum front setback: 50 ft (Unless special setback lines apply (see Chapter 18.58))
- Minimum side setback: 15 ft
- Minimum rear setback: 15 ft
- Maximum floor area ratio (FAR): 0.55
R-MF-23 (Multi-family residential zoning district) is a zoning district in Portola Valley. Every value below was read from the Portola Valley 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 R-MF-23
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 | 38 ft Applies: Principal Structure § 18.15.050 · code textTable row “Principal Structure”, column “R-MF-23”: Building height max. 38 ft/3 stories; Building height vertical: 34 ft |
|---|---|
| Maximum number of stories | 3 stories Applies: Principal Structure § 18.15.050 · code textTable row “Principal Structure”, column “R-MF-23”: Building height max. 38 ft/3 stories; Building height vertical: 34 ft |
| Minimum front setback | 50 ft Applies: Unless special setback lines apply (see Chapter 18.58) § 18.15.050 · code textTable row “Front”, column “R-MF-23”: 50 ft unless special setbacks apply, see Chapter 18.58—Special Setback Lines, 75 ft along Alpine Road |
| Minimum side setback | 15 ft § 18.15.050 · code textTable row “Interior Side”, column “R-MF-23”: Min. 15 ft |
| Minimum rear setback | 15 ft § 18.15.050 · code textTable row “Rear”, column “R-MF-23”: Min. 15 ft |
| Maximum floor area ratio (FAR) | 0.55 § 18.15.050 · code textTable row “Floor Area Ratio (FAR) 1”, column “R-MF-23”: Max. 0.55 |
When a different number applies
The code sets other values for particular lots, buildings or locations in R-MF-23:
- Minimum front setback: 75 ft — Along Alpine Road § 18.15.050
Not on this page
We did not find a general lot size, lot coverage, density limit for R-MF-23 in the zoning tables we read. The code may still set one elsewhere — check the Portola Valley Municipal Code.
Other Portola Valley zoning districts
Who this affects
Frequently asked questions
What is the maximum building height in Portola Valley's R-MF-23 zone?
38 ft (principal Structure) — Portola Valley Municipal Code § 18.15.050.
What is the maximum number of stories in Portola Valley's R-MF-23 zone?
3 stories (principal Structure) — Portola Valley Municipal Code § 18.15.050.
What is the minimum front setback in Portola Valley's R-MF-23 zone?
50 ft (unless special setback lines apply (see Chapter 18.58)) — Portola Valley Municipal Code § 18.15.050.
What is the minimum side setback in Portola Valley's R-MF-23 zone?
15 ft — Portola Valley Municipal Code § 18.15.050.
What is the minimum rear setback in Portola Valley's R-MF-23 zone?
15 ft — Portola Valley Municipal Code § 18.15.050.
General information, not legal advice.
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