85 Lancaster Ave
Kentfield 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.94919, -122.54284
Executive Verdict · Public-Records Synthesis
Zoned R1-B1 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood due diligence; benchmark value $2,433,000 ($2,141,000–$2,725,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone R1-B1 allows residential use qualifying for ministerial ADU review under state law (6 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$131,370 contributory est.)
Public building records show issued construction/renovation work on this parcel (8 total permits, latest Sep 8, 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
- ! FEMA Special Flood Hazard Area (AE, about 5% of the lot of lot)
Zone AE: 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)
- ! Delayed or open permit activity on this parcel
New garage / accessory structure (81915): Pending in review for 8.5 yr (18.9× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
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: Magnolia Village (0.26 mi S, entitled). 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 (~$28,430/yr at $2,433,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,369/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:
- 9,757 sq ft (0.22 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 85 LANCASTER AVE
Zoning & Land Use
R1-B1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned R1-B1, a single-family residential zone. FEMA Special Flood Hazard Area (Zone AE) covers about 5% 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 R1-B1, a single-family residential zone. The lot is 9,757 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 AE) covers about 5% 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
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone AE: 1% annual chance flood (Special Flood Hazard Area) (about 5% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 16% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 79% 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: $2,141,000 – $2,725,000 · 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
- Magnolia Village (Entitled)0.26 mi S
In "Entitled" for 3.8 yr (since Feb 1, 2023), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (20 housing units, 4 deed-restricted affordable across 0 permits).
- New garage / accessory structure (81915) (Applied)On this parcel
Pending in review for 8.5 yr (18.9× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
- New commercial building at 675 Sir Francis Drake Blvd (Issued)0.34 mi E
Active in "Issued" for 12.7 yr (first record Mar 6, 2014) with no new permit activity recorded in 12.5 yr. High-impact scale ($2,400,000 declared valuation across 2 permits).
- Accessory dwelling unit at 625 College Ave (a D U 627) (Issued)0.4 mi W
Active in "Issued" for 3.9 yr (first record Dec 7, 2022) with no new permit activity recorded in 3 yr. High-impact scale (1 housing unit, $4,500,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Owner Builder (1 on parcel, 44 in ½ mi · Remodel / interior alteration); Ernest Ongaro And Sons (1 on parcel, 2 in ½ mi · Accessory dwelling unit (new or conversion)); Towery Electric (2 on parcel, 2 in ½ mi · Electrical / panel); Ambrose Construction (1 on parcel, 1 in ½ mi · Solar / battery storage); North HVAC Services (1 on parcel, 1 in ½ mi · HVAC / heat pump).
Permit & Project History on This Parcel (8 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 182520 | Addition (adds square footage) | Issued | Iss. Sep 8, 2026 | $155,000 | Interior Remodel, Bathroom Addition And Remodel, Entryway Addition. (N) Office, (N) Lounge Area. |
| B32287 | HVAC / heat pump | Issued | Iss. Jan 16, 2023 | $11,950 | Replace gas furnace with electric heat pump system. — Mechanical Appliance |
| B30573 | Solar / battery storage | Issued | Iss. Aug 11, 2022 | $48,685 | 8.0750kW PV(19XSPRM-425-H-AC) ROOF MOUNT ON RES. INSTALLING TESLA AC PW(1X2012170-XX-Y) 5kW EACH |
| B30552 | HVAC / heat pump | Issued | Iss. Jul 29, 2022 | $11,700 | INSTALL DUCTED MINI SPLIT SYSTEM. SEER 14 — Replace Mechanical Appliance |
| B24881 | Plumbing / water heater / sewer |