166 A Seadrift Rd
Stinson Beach 94970 · Stinson Beach · Unincorporated Marin · Coordinates: 37.90515, -122.65920
Executive Verdict · Public-Records Synthesis
Zoned C-RSPS-2.9 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA VE flood / CAL FIRE high fire hazard severity zone (local responsibility area) due diligence; benchmark value $3,547,000 ($3,121,000–$3,973,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone C-RSPS-2.9 allows residential use qualifying for ministerial ADU review under state law (2 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$260,000 contributory est.)
Public building records show issued construction/renovation work on this parcel (3 total permits, latest Jan 23, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (VE, about 86% of the lot of lot)
Zone VE: 1% annual chance flood (Special Flood Hazard Area) overlaps this parcel. Expect mandatory flood insurance for federally backed loans and floodplain elevation/mitigation rules for new units or SB 9 applications.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! CAL FIRE High Fire Hazard Severity Zone (Local Responsibility Area) (about 50% 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
Addition (adds square footage) (93400): Pending in review for 16 mo (3.0× the 160d median) — slower than 90% of addition (adds square footage) permits in Unincorporated Marin (median 160d, 90th pct 440d, n=316).
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 150 Seadrift Rd (490 ft SE, 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:
- 29,142 sq ft (0.67 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 166A SEADRIFT RD; 166 SEADRIFT RD
Zoning & Land Use
C-RSPS-2.9 — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned C-RSPS-2.9 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned C-RSPS-2.9, a single-family residential zone. FEMA Special Flood Hazard Area (Zone VE) covers about 86% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
- SB 9: split into two lotsPossible, with conditions
Zoned C-RSPS-2.9, a single-family residential zone. The lot is 29,142 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. FEMA Special Flood Hazard Area (Zone VE) covers about 86% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (Local Responsibility Area) (about 50% of the lot, map Mar 24, 2025); Moderate Fire Hazard Severity Zone (Local Responsibility Area) (about 37% of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone VE: 1% annual chance flood (Special Flood Hazard Area) (about 86% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 14% of the lot) · FIRM panel 06041C0443E, effective August 15, 2017
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $3,121,000 – $3,973,000 · Status: Off market
HUD Small Area FMR (ZIP 94970) · FY 2026
Studio $2,090 · 1BR $2,510 · 2BR $3,030 · 3BR $3,870 · 4BR $4,010
Developments Deserving Closer Investigation & Active Area Builders
- Addition (adds square footage) (93400) (Applied)On this parcel
Pending in review for 16 mo (3.0× the 160d median) — slower than 90% of addition (adds square footage) permits in Unincorporated Marin (median 160d, 90th pct 440d, n=316).
- New home at 150 Seadrift Rd (Issued)490 ft SE
Active in "Issued" for 10.2 yr (first record Sep 6, 2016) with no new permit activity recorded in 9.9 yr. High-impact scale (1 housing unit, $1,750,000 declared valuation across 1 permit).
- New home at 182 Seadrift Rd (Issued)500 ft NW
Active in "Issued" for 5.9 yr (first record Dec 15, 2020) with no new permit activity recorded in 5.4 yr. High-impact scale (1 housing unit, $2,875,000 declared valuation across 1 permit).
- Accessory dwelling unit at 166 Seadrift Rd (a D U 166 A) (Issued)On this parcel
Active in "Issued" for 19 mo (first record Apr 7, 2025) with no new permit activity recorded in 10 mo.
Entity-resolved builders & contractors in ½ mile: George T Flynn Construction (1 on parcel, 3 in ½ mi · Accessory dwelling unit (new or conversion)); Baldwin Roofing (1 on parcel, 1 in ½ mi · Roof replacement); Gubbins Building (17 in ½ mi · Remodel / interior alteration); Allen Construction (8 in ½ mi · New garage / accessory structure); Matarozzi Pelsinger Builders (6 in ½ mi · Addition (adds square footage)).
Permit & Project History on This Parcel (3 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 180974 | Accessory dwelling unit (new or conversion) | Issued | Iss. Jan 23, 2026 | $550,000 | New Attached A D U; Hallway From A D U To Garage; Outdoor Shower; Window & Door Replacement |
| 93400 | Addition (adds square footage) | Applied | App. Jul 28, 2025 | $550,000 | Addition Of New A D U |
| B13543 | Roof replacement | Issued | Iss. Oct 19, 2017 | $18,785 | TEAR OFF TAR AND GRAVEL RE-ROOF CLASS A TAR AND GRAVEL — ReRoofing |