Multifamily and Duplex Properties for Sale in Tiburon: Zoning and Rent Rules

What multifamily in Tiburon looks like

Most of Tiburon is single-family hillside, so income property is a short list. You will find duplexes in the older R-2 blocks near downtown, small apartment and condominium buildings off Tiburon Boulevard and Main Street, units over downtown storefronts, and homes with an ADU or JADU. The 2023 downtown rezoning opened the door to denser mixed-use projects, so some commercial parcels now carry housing potential. For financing, see financing 2-4 unit properties and apartment building loans.

Where the zoning allows it

Tiburon is an incorporated town, and its residential zones are set out in Section 16-21. The downtown zones are in Division 16-23, adopted by Ordinance 605 N.S. on June 21, 2023.

New buildings in R-3, R-3-10 and R-4 need site plan and architectural review, which is design review rather than a use permit. The downtown zones set minimum densities as well as maximums, so a low-density rebuild on an MU or MS lot may not be approvable. On the Housing Element’s downtown sites, housing must make up half the floor area of a mixed-use project.

Affordable overlay. The NC/AHO overlay requires at least 5% very-low-, 10% low- and 10% moderate-income units, dropping to 20% total on sites of ten or fewer units. Units must be deed-restricted for at least 55 years. The Town offers incentives, including subsidies of up to 100% of special district hook-up fees.

SB 9. Tiburon’s two-unit housing chapter (16-77) was rewritten by Ordinance 612 on September 3, 2025. It applies only in single-family zones and allows two primary units. Units of 800 square feet or less with four-foot side and rear setbacks must be permitted. Rentals must run longer than 30 days. Parcels in a historic district, or taken off the rental market under the Ellis Act in the past 15 years, are excluded. See our SB 9 lot split guide.

ADUs. ADUs and JADUs are allowed in every residential and downtown zone under the Town’s ministerial permit. See our ADU investment guide.

Rent rules: state law only

Rent caps. The Attorney General’s rent cap page, updated July 16, 2026, places Marin County in the San Francisco Area region. The maximum increase for covered units is 6.3% from August 1, 2025, and 8.8% for increases from August 1, 2026 through July 31, 2027. The AG’s chart of local rent ordinances lists Larkspur in Marin, but not Tiburon. See our AB 1482 guide.

Just cause. Marin County’s just cause ordinance covers only unincorporated areas, so it does not reach property inside town limits. Covered Tiburon tenancies fall under the state’s just cause rules in AB 1482. See our just cause eviction guide.

Mediation. The county’s mandatory mediation program for increases over 5% covers only unincorporated Marin and San Rafael. Voluntary mediation is available in Tiburon.

Tiburon rental property rules

• Business license per unit. The Town’s business license page says anyone who owns a residential rental in Tiburon, from a single house to a multi-unit building, needs a license, charged per unit. A $14 administration and state fee is added.
• No vacation rentals. The residential use table states that vacation rentals are not permitted. A single-family home may take one paying guest for 31 days or more. Underwrite Tiburon units as long-term rentals.
• Transient occupancy tax. Chapter 7 defines a transient as a stay of 30 days or less and sets a tax of up to 10%.
• Transfer tax. The county charges $0.55 per $500 per the Recorder’s sheet, which lists only San Rafael as adding a city tax. Tiburon’s Chapter 8 sets $0.275 per $500, tied to the county ordinance. Confirm the total with escrow.

Sewer laterals, flood zones and older buildings

For property east of Gilmartin Drive, Sanitary District No. 5 requires a lateral inspection when a property is bought or sold, under Ordinance 2014-02a, effective March 4, 2015. A lateral replaced within the past 20 years, or inspected and repaired within three years, is exempt. West of Gilmartin, confirm which sewer agency serves the parcel and its rules.

Bayfront apartment parcels may fall in the Town’s flood overlay, which uses FEMA maps effective March 16, 2016. Get an elevation certificate and an insurance quote early. Many Tiburon apartment buildings are older wood-frame structures on slopes or fill, so a seismic retrofit review is worthwhile. Buildings of three or more units with elevated decks, common on view sites, need SB 721 balcony inspections.

Underwriting a Tiburon multifamily purchase

1. Confirm the zone and density. R-3 tops out at 12.4 units per acre, so many older buildings are legal nonconforming and may not rebuild at current unit counts.
2. Verify the permit history for every unit, including any ADU, JADU or SB 9 unit and its rental restrictions.
3. Classify each unit under AB 1482 and model increases at or below 8.8% for covered units.
4. Order the Sanitary District No. 5 lateral inspection where it applies, plus flood and seismic reviews.
5. Collect leases, the rent roll and estoppel certificates, and confirm the per-unit Town business license is current.
6. Rebuild expenses with reassessed property taxes, flood insurance and deck inspections in our rental property analysis.

Questions people ask

Sources & notes

1. Tiburon Section 16-21, Residential Zones (GoCodebook)
2. Tiburon Division 16-23, Downtown Zones
3. Tiburon Section 16-29, Overlay Zones
4. Tiburon Section 16-77, Two-Unit Housing Developments
5. Tiburon Chapter 7, TOT and Chapter 8, Transfer Tax
6. Town of Tiburon, Business Licenses
7. California Attorney General, Rent Caps
8. Marin County, Just Cause Eviction and Mandatory Mediation
9. Sanitary District No. 5, lateral inspections
10. Marin County Recorder, transfer tax

Note: We did not review the Town’s inclusionary chapter (16-70), its ADU standards text or any local seismic program, and found no Town rent or tenant chapter in the code index.

General information, not legal or tax advice. Last reviewed October 2026 by Matthew Martinez.

Related: Tiburon real estate guide · Commercial real estate in Tiburon · Multifamily investing guide · Investor services