228 Jamaica St
Tiburon 94920 · Paradise Cay · Unincorporated Marin · Coordinates: 37.91448, -122.47706
Executive Verdict · Public-Records Synthesis
Zoned RSP-5.8-BFC in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood due diligence; benchmark value $3,275,000 ($2,882,000–$3,668,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RSP-5.8-BFC allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$60,797 contributory est.)
Public building records show issued construction/renovation work on this parcel (5 total permits, latest Nov 19, 2025).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (AE, about 47% of the lot of lot)
Zone AE: 1% annual chance flood (Special Flood Hazard Area) overlaps this parcel. Expect mandatory flood insurance for federally backed loans and floodplain elevation/mitigation rules for new units or SB 9 applications.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! Delayed or open permit activity on this parcel
Electrical / panel (180532): Issued after 2 mo — slower than 90% of electrical / panel permits in Unincorporated Marin (median 0d, 90th pct 2d, n=3,019).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 4 slow or stalled nearby projects within ½ mile
Closest lead: New home at 149 Jamaica St (0.17 mi S, issued). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
- ! Year 1 Prop 13 tax reset (~$38,113/yr at $3,275,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$3,176/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 15,769 sq ft (0.36 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 228 JAMAICA ST
Zoning & Land Use
RSP-5.8-BFC — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RSP-5.8-BFC (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned RSP-5.8-BFC, a single-family residential zone. FEMA Special Flood Hazard Area (Zone AE) covers about 47% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
- SB 9: split into two lotsPossible, with conditions
Zoned RSP-5.8-BFC, a single-family residential zone. The lot is 15,769 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. FEMA Special Flood Hazard Area (Zone AE) covers about 47% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone AE: 1% annual chance flood (Special Flood Hazard Area) (about 47% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 53% of the lot) · FIRM panel 06041C0486E, effective March 16, 2016
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $2,882,000 – $3,668,000 · Status: Off market
HUD Small Area FMR (ZIP 94920) · FY 2026
Studio $2,820 · 1BR $3,380 · 2BR $4,100 · 3BR $5,230 · 4BR $5,420
Developments Deserving Closer Investigation & Active Area Builders
- Electrical / panel (180532) (Issued)On this parcel
Issued after 2 mo — slower than 90% of electrical / panel permits in Unincorporated Marin (median 0d, 90th pct 2d, n=3,019).
- Remodel / interior alteration (92394) (Applied)On this parcel
Pending in review for 2.3 yr (10.2× the 83d median) — slower than 90% of remodel / interior alteration permits in Unincorporated Marin (median 83d, 90th pct 266d, n=1,054).
- New home at 149 Jamaica St (Issued)0.17 mi S
Active in "Issued" for 12.2 yr (first record Aug 19, 2014) with no new permit activity recorded in 12 yr. High-impact scale (1 housing unit, $750,000 declared valuation across 1 permit).
- New home at 4970 Ranch Rd (Issued)0.38 mi NW
Active in "Issued" for 11.4 yr (first record Jun 2, 2015) with no new permit activity recorded in 11.2 yr. High-impact scale (1 housing unit, $1,200,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Owner (1 on parcel, 12 in ½ mi · Remodel / interior alteration); American Solar (2 on parcel, 2 in ½ mi · Solar / battery storage); Larkspur Builders (1 on parcel, 1 in ½ mi · Electrical / panel); Owner Builder (16 in ½ mi · Remodel / interior alteration); Davidson Builders (9 in ½ mi · New single-family home).
Permit & Project History on This Parcel (5 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 180532 | Electrical / panel | Issued | Iss. Nov 19, 2025 | $30,000 | Swim Spa |
| B44693 | Solar / battery storage | Issued | Iss. Nov 5, 2025 | $25,374 | Installation of (2) ESS Batteries |
| B41983 | Solar / battery storage | Issued | Iss. Apr 10, 2025 | $29,804 | 14.22kW Residential Roof-Mounted PV Array: (36) PV Modules w/ Microinverters, (1) PV AC Combiner, (1) FranklinWH aGate, … |
| 92394 | Remodel / interior alteration | Applied | App. Jul 15, 2024 | $750,000 | Remodel & Addition; Utility; Decks; Covered Entry; P V System 14.67 K W |
| 154757 | Remodel / interior alteration | Issued | Iss. Mar 15, 2017 |