Parcel Context · Public-Records Property BriefAPN 164-181-01
275 A Johnstone Dr
San Rafael 94903 · Marinwood · Unincorporated Marin · Coordinates: 38.04028, -122.53897
Parcel & Assessor
- Lot size:
- 10,280 sq ft (0.24 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 275A JOHNSTONE DR; 275 JOHNSTONE DR
Zoning & Land Use
R1-B2 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B2 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-B2, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B2, a single-family residential zone. The lot is 10,280 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (Local Responsibility Area) (all of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0291D, effective May 4, 2009
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
HUD Small Area FMR (ZIP 94903) · FY 2026
Studio $2,880 · 1BR $3,450 · 2BR $4,180 · 3BR $5,340 · 4BR $5,530
ACS 2020–2024 Median Gross Rent (Marinwood):$3,500+ Source: ACS 2020–2024 5-year estimates. Geography: Marinwood.
ACS 2020–2024 Median Gross Rent (ZIP 94903):$2,982±$267 Source: ACS 2020–2024 5-year estimates. Geography: San Rafael.
Zillow Home Value Index (ZIP 94903, September 2026):$1,250,063
ACS 2020–2024 Median Home Value (Marinwood):$1,267,000±$76,000 Source: ACS 2020–2024 5-year estimates. Geography: Marinwood.
ACS 2020–2024 Median Home Value (ZIP 94903):
Permit & Project History on This Parcel (2 permits, 1 grouped projects)
Accessory dwelling unit at 275 Johnstone DrStage: Issued · 1 units · $98,000 declared valuation · Last record Jul 16, 2026
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B48801 | Plumbing / water heater / sewer | Issued | Iss. Oct 16, 2026 | $12,335 | Replace Plumbing Fixtures(s) |
| 182126 | Accessory dwelling unit (new or conversion) | Issued | Iss. Jul 16, 2026 | $98,000 | Convert Part Of House To A D U; New Door; Landing |