12 Dipsea Trl
Mill Valley 94941 · Muir Woods Park · Unincorporated Marin · Coordinates: 37.90024, -122.55950
Executive Verdict · Public-Records Synthesis
Zoned RMP-0.5 in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE high fire hazard severity zone (state responsibility area) due diligence; benchmark value $2,309,000 ($2,032,000–$2,586,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-0.5 allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$24,096 contributory est.)
Public building records show issued construction/renovation work on this parcel (5 total permits, latest Feb 24, 2021).
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
Electrical / panel (162793): Issued after 3 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)
- ! 5 slow or stalled nearby projects within ½ mile
Closest lead: New home at 65 Ridge Ave (0.33 mi SW, 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:
- 27,704 sq ft (0.64 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 12 DIPSEA TRL
Zoning & Land Use
RMP-0.5 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-0.5 (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-0.5 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-0.5 (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 06041C0468F, 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: $2,032,000 – $2,586,000 · Status: Off market
HUD Small Area FMR (ZIP 94941) · FY 2026
Studio $2,730 · 1BR $3,270 · 2BR $3,960 · 3BR $5,060 · 4BR $5,240
Developments Deserving Closer Investigation & Active Area Builders
- New home at 65 Ridge Ave (Applied)0.33 mi SW
In "Applied" for 4 yr (since Oct 27, 2022), 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, $3,000,000 declared valuation across 1 permit).
- Electrical / panel (162793) (Issued)On this parcel
Issued after 3 mo — slower than 90% of electrical / panel permits in Unincorporated Marin (median 0d, 90th pct 2d, n=3,019).
- New home at 526 Panoramic Hwy (Issued)0.49 mi W
Active in "Issued" for 4.6 yr (first record Apr 21, 2022) with no new permit activity recorded in 2 yr. High-impact scale (1 housing unit, $1,329,450 declared valuation across 2 permits).
- Demolition at 688 Sequoia Valley Rd (Applied)0.18 mi S
In "Applied" for 3.2 yr (since Sep 6, 2023), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
Entity-resolved builders & contractors in ½ mile: Owner Builder (1 on parcel, 32 in ½ mi · Remodel / interior alteration); Robert Federighi (1 on parcel, 2 in ½ mi · Addition (adds square footage)); Capstone Roofing (1 on parcel, 1 in ½ mi · Roof replacement); J And J Electric (1 on parcel, 1 in ½ mi · Solar / battery storage); Gene Burch Plumbing Heating And Air (1 on parcel, 1 in ½ mi · HVAC / heat pump).
Permit & Project History on This Parcel (5 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 167239 | Remodel / interior alteration | Issued | Iss. Feb 24, 2021 | $40,946 | Rmdl Kitchen; (Repl Fireplace-Fireplace Remodel Not Allowed Removed From Scope Of Work) |
| B22493 | HVAC / heat pump | Issued | Iss. May 5, 2020 | $8,098 | replace AC unit — Replace Mechanical Appliance |
| 164023 | Solar / battery storage | Issued | Iss. Jan 23, 2020 | $16,416 | 4.8kw Roof Mount Photovoltaic - Express |
| B20630 | Roof replacement | Issued | Iss. Dec 18, 2019 | $26,700 | Tear-off & re-roof w/Class A Comp Shingles — ReRoofing |
| 162793 | Electrical / panel | Issued | Iss. Sep 30, 2019 |