Sonoma, CA Building Setbacks & Zoning: Lot Coverage Limits (2026)
Key Facts
- Governing table
- SMC 19.34.020(A), Table 3-27
- R-L zone site coverage
- 40%
- R-M zone site coverage
- 60%
- MX zone site coverage
- 70%
- Commercial zone site coverage
- 100%
- Scope
- Downtown district only, not citywide
Summary
In the City of Sonoma's Downtown district, SMC 19.34.020's dimensional table caps site coverage from 40 percent in the Residential-Low zone up to 100 percent in the Commercial zone, paired with floor-area-ratio limits ranging from 0.35 to 2.0. These figures apply only within the Downtown district's zoning designations, not citywide.
| " | R-L | R-M | R-O | MX | C | ... | F.A.R. | 0.35 | 0.50 | 0.70 | 1.20 | 2.0 | | Site Coverage | 40% | 60% | 65% | 70% | 100% |
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through Ordinance 13-2025, passed December 3, 2025).
Full Breakdown
Sonoma's Title 19 does not set one citywide lot coverage number; because the code is organized geographically by planning area and district, each area carries its own dimensional table. 020(A) sets site coverage by zoning district: 40 percent in the Residential-Low (R-L) zone, 60 percent in Residential-Medium (R-M), 65 percent in Residential-Housing Opportunity (R-O), 70 percent in Mixed Use (MX), and 100 percent in Commercial (C). 0 in C. 150(A)(5), as the percentage of the total site occupied by structures, including the residential units, garage, accessory buildings, decks more than 18 inches above grade, and any area needed for vehicle ingress, egress, parking, and circulation.
080 set minimum open space by unit type separately for multifamily and for commercial or mixed-use projects. A property owner in a different planning area, such as Broadway Corridor or one of the outlying residential subareas, needs that area's own chapter and table, since a Downtown coverage percentage does not transfer to another part of the city.
Violations & Fines
Constructing beyond the applicable site coverage or FAR limit without approval is a development code violation under SMC 19.90.040: it is declared a public nuisance and a misdemeanor, and the city planner can issue a stop-work order and later charge the property owner for the city's administrative abatement costs under SMC 19.90.100.
Frequently Asked Questions
What is the maximum lot coverage in Downtown Sonoma?
Is there one citywide lot coverage limit in Sonoma?
What counts toward site coverage in Sonoma?
Sources & Official References
Other rules in Sonoma
California rules heatmap·Compare Sonoma to another location·View the California building setbacks & zoning overview
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Lot Coverage Limits in Nearby Cities
How other cities in Sonoma County handle lot coverage limits.