1351 Idylberry Rd
San Rafael 94903 · Lucas Valley · Unincorporated Marin · Coordinates: 38.03575, -122.58264
Executive Verdict · Public-Records Synthesis
Zoned R1-B-LV in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE high fire hazard severity zone (local responsibility area) due diligence; benchmark value $1,407,000 ($1,238,000–$1,576,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1-B-LV supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 9,496 sq ft lot. Local precedent is active with 2 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$8,088 contributory est.)
Public building records show issued construction/renovation work on this parcel (8 total permits, latest Jan 7, 2025).
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 (Local 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 Mar 24, 2025)
- ! Delayed or open permit activity on this parcel
Solar / battery storage (83786): Pending in review for 7.4 yr — slower than 90% of solar / battery storage permits in Unincorporated Marin (median 0d, 90th pct 2d, n=2,977).
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: Accessory dwelling unit at 42 Oak Mountain Ct (0.14 mi S, applied). 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:
- 9,496 sq ft (0.22 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 1351 IDYLBERRY RD
Zoning & Land Use
R1-B-LV — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B-LV (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-B-LV, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B-LV, a single-family residential zone. The lot is 9,496 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 06041C0287D, effective May 4, 2009
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,238,000 – $1,576,000 · 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
- Solar / battery storage (83786) (Applied)On this parcel
Pending in review for 7.4 yr — slower than 90% of solar / battery storage permits in Unincorporated Marin (median 0d, 90th pct 2d, n=2,977).
- Accessory dwelling unit at 42 Oak Mountain Ct (Applied)0.14 mi S
In "Applied" for 5.5 yr (since Apr 30, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- Demolition at 2000 Lucas Valley Rd (Applied)0.25 mi S
In "Applied" for 4.4 yr (since Jun 7, 2022), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
- Accessory dwelling unit at 1 Golden Lily Pl (Applied)0.27 mi W
In "Applied" for 4.8 yr (since Jan 20, 2022), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Entity-resolved builders & contractors in ½ mile: Gawronski Tom Construction (3 on parcel, 3 in ½ mi · Windows / doors / siding); Solarcraft Services (2 on parcel, 2 in ½ mi · Electrical / panel); Wedge Roofing (1 on parcel, 1 in ½ mi · Roof replacement); Moore Heating Air And Solar (1 on parcel, 1 in ½ mi · Solar / battery storage); John Owens Services (1 on parcel, 1 in ½ mi · Plumbing / water heater / sewer).
Permit & Project History on This Parcel (8 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B40755 | Plumbing / water heater / sewer | Issued | Iss. Jan 7, 2025 | $9,341 | SFD - Install 65 gal HPWH same location in the garage — Replace Plumbing Fixtures(s) |
| 163729 | Electrical / panel | Issued | Iss. Dec 26, 2019 | $2,000 | Main Panel Upgrade |
| 161967 | Solar / battery storage | Issued | Iss. Jul 3, 2019 | $24,963 | Pv Solar 4.65kw - Express |
| 83786 | Solar / battery storage | Applied | App. Jun 27, 2019 | $24,963 | Rooftop P V 4.65 K W - Fast Trak |
| B17861 | Roof replacement | Issued | Iss. May 28, 2019 | $33,775 |