High-Density Mixed-Use
and Multi-Family Districts,
and Zoning Code Updates,
Ordinance Introduction
September 8, 2026
Shelby Donohoe, Senior Planner
Community Development
1 Presentation Overview
Background
Zone District Updates
• R6 High Density Multiple Family Residential
• R7 High Density Multiple Family Residential
• MU3 Medium Density Mixed-Use
• MU4 High Density Mixed-Use
Additional Code Updates
FAR Discussion
Recommendation
2 General Plan and
Zoning Code Update
General Plan 2040
- Strategic document adopted 2024
- High-level policy direction
- Overall development intensity and land
use patterns
Zoning Code (SMMC Title 27)
- Enforceable development standards
- Currently undergoing a comprehensive
update to better align with General
Plan goals and policies
- Anticipated completion mid 2027
3 Proposed Districts
State Law
Local ADU Ordinance
• California State Legislature establishes state-wide ADU laws • HCD has authority to enforce State ADU Laws & review local ordinances for compliance
• San Mateo adopted an updated local ADU Ordinance in 2022 • Builds upon State Law to regulate ADU development in the City • Currently being updated to reflect changes to State Law and local needs
Proposed Zone District General Plan Designation
R6 High Density Multiple Family Residential Residential Medium II R7 High Density Multiple Family Residential Residential High MU3 Medium Density Mixed-Use Mixed-Use Medium II
MU4 High Density Mixed-Use Mixed-Use High
4 Development Standard R6 Proposed Requirement
Maximum Density 99 dwelling units per acre
Floor Area Ratio 3.5
Maximum Height 6 Stories / 75 ft
Front Yard Setback None Required
Side Yard Setback None Required
Rear Yard Setback 5 ft
Buffers Adjacent to R1 or R2 Districts Side: 10 ft
Rear: 15 ft
R6 DISTRICT
HIGH DENSITY
MULTIPLE FAMILY
RESIDENTIAL
Accommodates higher-density multi-family housing
in appropriate locations, particularly along major
corridors and near mixed-use, employment and
commercial areas.
5 R7 DISTRICT
HIGH DENSITY
MULTIPLE FAMILY
RESIDENTIAL
Accommodates the City’s highest-density
residential development in locations with the
greatest access to transit, services, employment
centers, and commercial uses.
Development Standard R7 Proposed Requirement
Maximum Density 130 dwelling units per acre
Floor Area Ratio 4.0
Maximum Height 8 Stories / 100 ft
Front Yard Setback None Required
Side Yard Setback None Required
Rear Yard Setback 5 ft
Buffers Adjacent to R1 or R2
Districts
Side: 10 ft
Rear: 15 ft
6 MU3 MEDIUM DENSITY
MIXED-USE
Accommodates a wide range of commercial,
office, and civic uses along with multi-family
residential units in order to promote diverse
walkable development.
Development Standard MU3 Proposed Requirement
Maximum Density (Residential) 99 dwelling units per acre Minimum Density (Mixed-Use with
Residential)
50 units per acre when within ½-mile of a Caltrain Station 30 units per acre when beyond ½-mile of a Caltrain Station Per Section 27.02.230.
Floor Area Ratio 4.0
Maximum Height Nonresidential: 4 Stories (50 ft)
Mixed-Use with Residential: 6 Stories (75 ft)
Front Yard Setback None Required
Side Yard Setback None Required
Rear Yard Setback 5 ft
Buffers Adjacent to R1 or R2 Districts Side: 10 ft
Rear: 15 ft
7 MU4 HIGH DENSITY
MIXED-USE
Accommodates the same range of commercial, office,
institutional, and residential uses allowed in the MU3
District, but at increased intensity to support a more
concentrated mix of uses.
Development Standard MU4 Proposed Requirement
Maximum Density (Residential) 130 dwelling units per acre Minimum Density (Mixed-Use with
Residential) 50 units per acre per Section 27.02.230.
Floor Area Ratio 4.5
Maximum Height Nonresidential: 5 Stories (65 ft)
Mixed-Use with Residential: 8 Stories (100 ft)
Front Yard Setback None Required
Side Yard Setback None Required
Rear Yard Setback 5 ft
Buffers Adjacent to R1 or R2 Districts Side: 10 ft
Rear: 15 ft
8 Height Standards Methodology
District Height Limit
R6 Six Stories / 75 feet
R7 Eight Stories / 100 feet
MU3 Nonresidential: Four Stories / 50 Feet
Mixed-Use with Residential: Six Stories / 75 Feet
MU4 Nonresidential: Five Stories / 65 Feet
Mixed-Use with residential: Eight Stories / 100 Feet
• Methodology for translating stories to a height limit • First Story – 14 ft (floor to floor)
• Upper Stories 12 ft (floor to floor)
• Function as interim height limits
• Final height limits to established as part of Comprehensive Zoning Code Update
9 General Plan Policy LU 2.3 informed proposed two-
tier height limits in Mixed-Use Districts
• Aligns with goal to incentivize housing in mixed-use
development
• Supports a future community benefits framework
Height Standards within
Mixed-Use Districts
10 State Law
Additional Discussion:
Floor Area Ratio (FAR) Maximums for Residential Uses
Staff requests direction from City Council on applicability of FAR maximums as applied to residential uses.
Floor Area Ratio R6
The maximum floor area ratio of buildings and structures on a zoning plot shall be 3.5. [Alternative Proposal: remove this section and renumber chapter.] Floor Area Ratio R7
The maximum floor area ratio of buildings and structures on a zoning plot shall be 4.0. [Alternative Proposal: remove this section and renumber chapter.] Floor Area Ratio MU3
The maximum floor area ratio of buildings and structures on a zoning plot shall be 4.0. [Alternative Proposal: add following text "Floor area ratio shall only apply to nonresidential portions of a building".] Floor Area Ratio MU4
The maximum floor area ratio of buildings and structures on a zoning plot shall be 4.5. [Alternative Proposal: add following text "Floor area ratio shall only apply to nonresidential portions of a building".] 11 Projects within the Proposed Districts would be required to provide open space as follows:
• 50 square feet of private open space per unit; or
• 75 square feet of common open space per unit; or
• A combination of private and common usable open
space:
• Min. 30 square feet of private usable open space per
unit. The remaining open space obligation can be met
through common usable open space equal to 150 percent
remaining private open space requirement.
Open Space Standards
within Proposed Districts
12 Additional Code Amendments
Landscape Code Revision – Exempting 100%
affordable housing developments from landscape
code requirements.
SPAR Requirement – Removing language related
to City Council review requirement for buildings above
55 feet in height.
13 Additional Code Amendments
Commercial Zone Districts – Clarifying that residential uses within commercial districts shall take place above the ground floor.
Residential References within Non-Residential
Districts – Correcting cross references within the code to residential development standards.
14 Additional Code Amendments
Permitted Uses within C4 Zone District, CBD
Zone District and E2 Zone District – Reinstating uses
within these districts that were previously
unintentionally removed.
Temporary Construction Uses –Adding temporary
buildings for construction purposes as a permitted use
to amended districts.
15 Additional Code Amendments
Retail FAR standards - Removing double FAR calculation
for ground floor commercial spaces over 18' in height.
In-Person Sale Requirements - Removing requirement
that businesses within the required retail frontage zone do over 50% of sales in-person.
16 State Law
Local ADU Ordinance
• California State Legislature establishes state-wide ADU laws • HCD has authority to enforce State ADU Laws & review local ordinances for compliance
Public Hearing on June 23, 2026 - Commission recommended that City Council adopt the proposed ordinance, with an FAR requirement that excluded residential uses.
A Study Session was requested on the proposed districts to further discuss the high density requirements.
• Planned for later this year, ahead of publication of the draft of the Comprehensive Zoning Code.
Planning Commission
17 State Law
Local ADU Ordinance
• California State Legislature establishes state-wide ADU laws • HCD has authority to enforce State ADU Laws & review local ordinances for compliance
• San Mateo adopted an updated local ADU Ordinance in 2022 • Builds upon State Law to regulate ADU development in the City • Currently being updated to reflect changes to State Law and local needs
The proposed Ordinance is statutorily exempt from the
requirements of the California Environmental Quality Act pursuant to Section 21080.17 of the Public Resources Code and Section 15183 of the CEQA Guidelines.
CEQA
18 State Law
Local ADU Ordinance
• California State Legislature establishes state-wide ADU laws • HCD has authority to enforce State ADU Laws & review local ordinances for compliance
• San Mateo adopted an updated local ADU Ordinance in 2022 • Builds upon State Law to regulate ADU development in the City • Currently being updated to reflect changes to State Law and local needs
Introduce an Ordinance to make various amendments to Title 27 “Zoning” of the San Mateo Municipal Code to establish four new high density zoning districts consistent with General Plan 2040 and make minor revisions to various sections to update outdated language and correct inconsistencies.
• Should any updates be made to the Floor Area Ratio
(FAR) requirements?
Recommendation
19 Backup Slides
20 21
(a) Permitted uses in the C1, C2, and C3 districts, except that residential uses, low barrier navigation centers, office uses on the properties along Palm Avenue between Twentieth and Twenty-fifth Avenues, and emergency shelters are prohibited;
(b) Air conditioning and heating sales and service;
(c) Animal hospitals, which may include outdoor kennels; (d) Automotive parts, service, and repair classified as major motor vehicle repair in Section 27.04.320; (e) Construction materials sales and lumberyards;
(f) Dry cleaning establishments, without customer service areas; (g) Linen, towel, diaper and other similar supply services; (h) Machinery sales, rental, and service, when conducted within an enclosed building; (i) Parcel delivery and receiving stations;
(j) Processing and assembly of goods determined by the Zoning Administrator to be compatible with adjacent uses, provided that space in a building does not exceed six thousand square feet of total floor area and basement space, not including stairwells or elevator shafts; and provided that such processing or assembly can be conducted without noise, vibration, order, dust or any other condition which might be disturbing to occupants of adjacent buildings.
When manufacturing operations of the same or similar products demand space exceeding six thousand square feet, they shall be located in the M1 district.
(k) Sheet metal shops;
(l) Storage and warehousing;
(m) Tool, die and pattern making;
(n) Welding and iron work;
(o) Wholesale establishments;
(p) Accessory to principal uses permitted;
(q) Other compatible uses as determined by the Zoning Administrator.