51 Erin Dr
San Rafael 94903 · Marinwood · Unincorporated Marin · Coordinates: 38.02566, -122.54397
Executive Verdict · Public-Records Synthesis
Zoned RMP-1.38 in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE high fire hazard severity zone (state responsibility area) due diligence; benchmark value $1,316,000 ($1,158,000–$1,474,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-1.38 allows residential use qualifying for ministerial ADU review under state law (10 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$7,680 contributory est.)
Public building records show issued construction/renovation work on this parcel (4 total permits, latest Aug 7, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! Mapped flood awareness zone (Zone X: minimal flood hazard)
all of the lot of the parcel intersects Zone X: minimal flood hazard. Outside mandatory federal SFHA insurance rules, but check local drainage and finished-floor requirements.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! CAL FIRE High Fire Hazard Severity Zone (State Responsibility Area) (all of the lot of lot)
Located in a mapped Fire Hazard Severity Zone. Expect Chapter 7A ignition-resistant building standards, defensible-space inspections, and stricter property insurance underwriting.
Source: CAL FIRE FHSZ (map Apr 1, 2024)
- ! Delayed or open permit activity on this parcel
New home at 51 Erin Dr: Active in "Issued" for 3 yr (first record Oct 25, 2023) with no new permit activity recorded in 20 mo.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 5 slow or stalled nearby projects within ½ mile
Closest lead: Los Gamos Apartments (0.48 mi S, entitled). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
Parcel & Assessor
- Lot size:
- 10,193 sq ft (0.23 ac)
- Assessor use:
- Single Family Attached
- Addresses on lot:
- 51 ERIN DR
Zoning & Land Use
RMP-1.38 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-1.38 (multifamily residential): state law allows ADUs where homes are allowed. On a multifamily lot the state allowance is different: ADUs in non-living space of the building, plus up to eight detached ADUs.
- SB 9: two homes on the lotUnlikely
Zoned RMP-1.38 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-1.38 (multifamily residential), not a single-family residential zone.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (State Responsibility Area) (all of the lot, map Apr 1, 2024)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0293E, 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: $1,158,000 – $1,474,000 · Status: Off market
HUD Small Area FMR (ZIP 94903) · FY 2026
Studio $2,880 · 1BR $3,450 · 2BR $4,180 · 3BR $5,340 · 4BR $5,530
Developments Deserving Closer Investigation & Active Area Builders
- Los Gamos Apartments (Entitled)0.48 mi S
In "Entitled" for 4.8 yr (since Feb 7, 2022), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (192 housing units, 20 deed-restricted affordable across 0 permits).
- New home at 51 Erin Dr (Issued)On this parcel
Active in "Issued" for 3 yr (first record Oct 25, 2023) with no new permit activity recorded in 20 mo.
- New home at 118 Erin Ct (Applied)0.19 mi NW
In "Applied" for 3 yr (since Nov 28, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121). High-impact scale (1 housing unit, $55,415,888 declared valuation across 1 permit).
- New home at 115 Erin Ct (Applied)0.2 mi NW
In "Applied" for 3 yr (since Nov 28, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121). High-impact scale (1 housing unit, $55,415,888 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Haven Construction (2 on parcel, 17 in ½ mi · Accessory dwelling unit (new or conversion)); Solarpark USA (1 on parcel, 1 in ½ mi · Other); Secutech (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner Builder (11 in ½ mi · Accessory dwelling unit (new or conversion)); Owner (5 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B47785 | Other | Issued | Iss. Aug 7, 2026 | $6,300 | — |
| B42236 | Solar / battery storage | Issued | Iss. May 1, 2025 | $6,000 | Rooftop mounted PV system 2.835kw |
| 178909 | New single-family home | Issued | Iss. Mar 26, 2025 | $397,736 | S F D, Garage, Cvrd Porch Plan 6 B |
| 178475 | General repair | Issued | Iss. Jan 17, 2025 | $17,964 | Retaining Wall |
State HCD Housing Element APR records on this parcel: 1 entry (report years 2025).