Palo Alto RM-40 zoning: height, setbacks and lot size

RM-40 is a zoning district in Palo Alto. Every value below was read from the Palo Alto 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 RM-40

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	40 ft § 18.13.040 · code text Table row “Maximum Height (ft)”, column “RM-40”: 40
Minimum front setback	20 ft See note 2 below the table in the code. § 18.13.040 · code text Table row “Front Yard (ft)”, column “RM-40”: 20 (2) Note 2: Lesser setbacks may be allowed by the Planning Director, upon recommendation by the Architectural Review Board pursuant to criteria set forth in Chapter 18.76 and the context-based criteria outlined in Section 18.13.060. Special setbacks may not be reduced except upon approval of a design enhancement exception or variance.
Minimum side setback	10 ft § 18.13.040 · code text Table row “For lots with width of 70 feet or greater”, column “RM-40”: 10
Minimum rear setback	10 ft § 18.13.040 · code text Table row “Interior Rear Yards (ft) 3”, column “RM-40”: 10
Minimum lot size	8,500 sq ft § 18.13.040 · code text Table row “Site Area (ft 2 )”, column “RM-40”: 8,500
Maximum lot coverage	45% § 18.13.040 · code text Table row “Base”, column “RM-40”: 45%
Maximum floor area ratio (FAR)	1.0:1 See note 4 below the table in the code. § 18.13.040 · code text Table row “Maximum Floor Area Ratio (FAR) (4)”, column “RM-40”: 1.0:1 Note 4: Covered parking is not included as floor area in multi-family development, up to a maximum of 230 square feet per required parking space that is covered. Covered parking spaces in excess of required parking spaces count as floor area.
Maximum density	40 units per acre See note 3 below the table in the code. § 18.13.040 · code text Table row “Maximum number of units per acre (3)”, column “RM-40”: 40 Note 3: Provided that, for any lot of 5,000 square feet or greater, two units are allowed, subject to compliance with all other development regulations.

When a different number applies

The code sets other values for particular lots, buildings or locations in RM-40:

Maximum building height: 35 ft — Portions of a site within 50 feet of a more restrictive residential district or a site containing a residential use in a nonresidential district § 18.13.040
Minimum front setback: 25 ft — On arterial roadways, expressways, and freeways; the Planning Director may allow a lesser setback § 18.13.040
Minimum side setback: 6 ft — For lots with width of less than 70 feet § 18.13.040
Maximum floor area ratio (FAR): 1.25:1 — Housing development project of eight to ten units; not in a historic district or on a historic inventory § 18.13.045

Not on this page

We did not find a general stories limit for RM-40 in the zoning tables we read. The code may still set one elsewhere — check the Palo Alto Municipal Code.

Other Palo Alto zoning districts

Who this affects

HomeownersArchitects and designersDevelopersReal estate agents

Frequently asked questions

What is the maximum building height in Palo Alto's RM-40 zone?

40 ft — Palo Alto Municipal Code § 18.13.040.

What is the minimum front setback in Palo Alto's RM-40 zone?

20 ft — Palo Alto Municipal Code § 18.13.040.

What is the minimum side setback in Palo Alto's RM-40 zone?

10 ft — Palo Alto Municipal Code § 18.13.040.

What is the minimum rear setback in Palo Alto's RM-40 zone?

10 ft — Palo Alto Municipal Code § 18.13.040.

What is the minimum lot size in Palo Alto's RM-40 zone?

8,500 sq ft — Palo Alto Municipal Code § 18.13.040.

General information, not legal advice.