317 Durant Way
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.87121, -122.53033
Executive Verdict · Public-Records Synthesis
Zoned RMP-2.5 in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE high fire hazard severity zone (state responsibility area) due diligence; benchmark value $2,086,000 ($1,836,000–$2,336,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-2.5 allows residential use qualifying for ministerial ADU review under state law (1 ADU permit permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$47,663 contributory est.)
Public building records show issued construction/renovation work on this parcel (8 total permits, latest Nov 1, 2024).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Tamalpais
50 substantial renovation & housing permits over 24 months (20.5 per 1,000 parcels vs. 16.4 citywide baseline) (#3 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Tamalpais)
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
Solar / battery storage (92019): Pending in review for 2.6 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)
- ! 4 slow or stalled nearby projects within ½ mile
Closest lead: New home at 535 Tennessee Valley Rd (adu 531) (0.25 mi E, 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)
Parcel & Assessor
- Lot size:
- 5,009 sq ft (0.11 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 317 DURANT WAY
Zoning & Land Use
RMP-2.5 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-2.5 (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-2.5 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-2.5 (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 06041C0507E, 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: $1,836,000 – $2,336,000 · 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
- Solar / battery storage (92019) (Applied)On this parcel
Pending in review for 2.6 yr — slower than 90% of solar / battery storage permits in Unincorporated Marin (median 0d, 90th pct 2d, n=2,977).
- Other (80706) (Applied)On this parcel
Pending in review for 9.2 yr — slower than 90% of other permits in Unincorporated Marin (median 0d, 90th pct 71d, n=1,560).
- New home at 535 Tennessee Valley Rd (adu 531) (Issued)0.25 mi E
Active in "Issued" for 6 yr (first record Oct 29, 2020) with no new permit activity recorded in 4 yr. High-impact scale (1 housing unit, $800,000 declared valuation across 1 permit).
- Accessory dwelling unit at 318 Via Recodo (Applied)0.16 mi SW
In "Applied" for 7.4 yr (since Jun 25, 2019), 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: Owner (2 on parcel, 19 in ½ mi · Remodel / interior alteration); Axia Solar (2 on parcel, 2 in ½ mi · Solar / battery storage); Infinity Energy (1 on parcel, 1 in ½ mi · Solar / battery storage); Freedom Forever (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner Builder (21 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (8 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B40042 | Solar / battery storage | Issued | Iss. Nov 1, 2024 | $700 | new 125 sub panel where the PV will be interconnected an addition to approved solar permit for permit #B37412 — Service … |
| B37412 | Solar / battery storage | Issued | Iss. Mar 21, 2024 | $32,262 | Roof top solar installation 27 panels+ 27 microinverters SYSTEM CAPACITY: 10.800 kW-DC 7.830 kW-AC (NAME PLATE) |
| 92019 | Solar / battery storage | Applied | App. Mar 20, 2024 | — | Rooftop Pv |
| B33446 | Solar / battery storage | Issued | Iss. Apr 14, 2023 | $28,000 | PV roof mount 11.20kW 28 panels |
| B33344 | Solar / battery storage | Issued |