21 Acorn Way
Kentfield 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.95091, -122.56188
Executive Verdict · Public-Records Synthesis
Zoned RSP-1 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE moderate fire hazard severity zone (state responsibility area) due diligence; benchmark value $2,571,000 ($2,262,000–$2,880,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned RSP-1 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 32,322 sq ft lot. Local precedent is active with 7 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$102,201 contributory est.)
Public building records show issued construction/renovation work on this parcel (6 total permits, latest Jun 23, 2025).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Kentfield
103 substantial renovation & housing permits over 24 months (40.9 per 1,000 parcels vs. 16.3 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 (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
General repair (93016): Pending in review for 20 mo (7.4× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 3 slow or stalled nearby projects within ½ mile
Closest lead: Accessory dwelling unit at 432 Woodland Rd (380 ft 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:
- 32,322 sq ft (0.74 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 21 ACORN WAY
Zoning & Land Use
RSP-1 — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RSP-1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned RSP-1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned RSP-1, a single-family residential zone. The lot is 32,322 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Moderate 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 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: $2,262,000 – $2,880,000 · 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 432 Woodland Rd (Applied)380 ft SW
In "Applied" for 2.6 yr (since Apr 12, 2024), 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, $1,250,000 declared valuation across 1 permit).
- General repair (93016) (Applied)On this parcel
Pending in review for 20 mo (7.4× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
- Pool / spa (93015) (Applied)On this parcel
Pending in review for 20 mo (4.5× the 136d median) — slower than 90% of pool / spa permits in Unincorporated Marin (median 136d, 90th pct 393d, n=162).
- New garage / accessory structure (93006) (Applied)On this parcel
Pending in review for 20 mo (3.8× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
Entity-resolved builders & contractors in ½ mile: Owner (1 on parcel, 7 in ½ mi · Remodel / interior alteration); Robert Federighi (1 on parcel, 1 in ½ mi · Remodel / interior alteration); Solarcraft Services (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner Builder (29 in ½ mi · Remodel / interior alteration); Hendrickson Pools (12 in ½ mi · Pool / spa).
Permit & Project History on This Parcel (6 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B42837 | Plumbing / water heater / sewer | Issued | Iss. Jun 23, 2025 | $9,745 | Increasing existing gas line. Installing new tankless water heater (Navien NPE-210A2) — Replace Plumbing Fixtures(s) |
| 93016 | General repair | Applied | App. Mar 5, 2025 | — | Retaining Walls |
| 93015 | Pool / spa | Applied | App. Mar 5, 2025 | — | Remodel Pool |
| 93006 | New garage / accessory structure | Applied | App. Feb 28, 2025 | — | Detached Poolhouse; Trellis, Outdoor Kitchen |
| B32817 | Solar / battery storage | Issued | Iss. Mar 2, 2023 | $35,860 |