27 Madrone Ave
Kentfield 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.96239, -122.54382
Executive Verdict · Public-Records Synthesis
Zoned RR-B3 in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE moderate fire hazard severity zone (local responsibility area) due diligence; benchmark value $2,703,000 ($2,379,000–$3,027,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RR-B3 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 (+$234,320 contributory est.)
Public building records show issued construction/renovation work on this parcel (11 total permits, latest Feb 25, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Kentfield
104 substantial renovation & housing permits over 24 months (41.3 per 1,000 parcels vs. 16.4 citywide baseline) (#7 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Kentfield)
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 Moderate 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)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: Accessory dwelling unit at 66 Hanken Dr (adu 66a) (0.31 mi SW, 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)
- ! Year 1 Prop 13 tax reset (~$31,535/yr at $2,703,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,628/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 25,265 sq ft (0.58 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 27 MADRONE AVE
Zoning & Land Use
RR-B3 — Residential Restricted (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RR-B3 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotCan't tell
Zoned RR-B3 (single-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential agriculture, estate and restricted: large-lot residential; confirm SB 9 with the county.
- SB 9: split into two lotsCan't tell
Zoned RR-B3 (single-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential agriculture, estate and restricted: large-lot residential; confirm SB 9 with the county.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Moderate 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 06041C0458F, 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: $2,379,000 – $3,027,000 · Status: Off market
HUD Small Area FMR (ZIP 94904) · FY 2026
Studio $2,260 · 1BR $2,710 · 2BR $3,280 · 3BR $4,190 · 4BR $4,340
Developments Deserving Closer Investigation & Active Area Builders
- Accessory dwelling unit at 66 Hanken Dr (adu 66a) (Issued)0.31 mi SW
Active in "Issued" for 3.1 yr (first record Sep 29, 2023) with no new permit activity recorded in 2.8 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
- New home at 138 Cypress Ave (Issued)0.42 mi SE
Active in "Issued" for 8.6 yr (first record Apr 23, 2018) with no new permit activity recorded in 8.2 yr. High-impact scale (1 housing unit, $1,020,000 declared valuation across 2 permits).
- New home at 49 Laurel Grove Ave (Issued)0.44 mi S
Active in "Issued" for 9.3 yr (first record Jul 18, 2017) with no new permit activity recorded in 9.1 yr. High-impact scale (1 housing unit, $1,200,000 declared valuation across 1 permit).
- New home at 29 Mann Dr (Issued)0.44 mi SE
Active in "Issued" for 12.7 yr (first record Mar 6, 2014) with no new permit activity recorded in 12.4 yr. High-impact scale (1 housing unit, $1,030,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: G Family Construction (1 on parcel, 5 in ½ mi · Addition (adds square footage)); Slm Builders (3 on parcel, 4 in ½ mi · Pool / spa); Dan Fix Enterprises (2 on parcel, 2 in ½ mi · General repair); Earthwise Energy Solutions (2 on parcel, 2 in ½ mi · Solar / battery storage); Yust Dba Acustruct (1 on parcel, 1 in ½ mi · General repair).
Permit & Project History on This Parcel (11 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 181160 | General repair | Issued | Iss. Feb 25, 2026 | $45,000 | Replace (E) Retaining Walls |
| 174284 | Pool / spa | Issued | Iss. Jun 14, 2023 | $25,000 | In-Ground Spa, Separate From Pool |
| 174283 | New garage / accessory structure | Issued | Iss. Jun 14, 2023 | $75,000 | Replace & Expand Pool Utilities Bldg; Add Bath & Operable Trellis/Covered Porch. Solar Is Deferred Submittal |
| 174282 | Pool / spa | Issued | Iss. Jun 14, 2023 | $150,000 | Replace & Reconfigure Pool |
| 163510 | General repair | Issued | Iss. Dec 11, 2019 | $30,000 |