33 Rosebank Ave
Kentfield 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.95232, -122.54365
Executive Verdict · Public-Records Synthesis
Zoned R1-B1 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,418,000 ($2,128,000–$2,708,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1-B1 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 11,892 sq ft lot. Local precedent is active with 8 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$81,066 contributory est.)
Public building records show issued construction/renovation work on this parcel (3 total permits, latest Apr 20, 2023).
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: 0.2% annual chance flood hazard (shaded X))
about 2% of the lot of the parcel intersects Zone X: 0.2% annual chance flood hazard (shaded X). Outside mandatory federal SFHA insurance rules, but check local drainage and finished-floor requirements.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: Magnolia Village (0.47 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 (~$28,257/yr at $2,418,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,355/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:
- 11,892 sq ft (0.27 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 33 ROSEBANK 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 lotLikely eligible
Zoned R1-B1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B1, a single-family residential zone. The lot is 11,892 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
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone X: 0.2% annual chance flood hazard (shaded X) (about 2% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 97% 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: $2,128,000 – $2,708,000 · 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)0.47 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).
- Accessory dwelling unit at 34 Wolfe Grade (Applied)0.46 mi NE
In "Applied" for 2.8 yr (since Jan 17, 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, $750,000 declared valuation across 1 permit).
- New home at 105 Oak Ave (Issued)0.21 mi N
Active in "Issued" for 4.3 yr (first record Jul 15, 2022) with no new permit activity recorded in 14 mo. High-impact scale (1 housing unit, $965,000 declared valuation across 3 permits).
- New home at 49 Laurel Grove Ave (Issued)0.29 mi N
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).
Entity-resolved builders & contractors in ½ mile: Michael Stone (2 on parcel, 5 in ½ mi · Remodel / interior alteration); Spryscapes Const (1 on parcel, 1 in ½ mi · Remodel / interior alteration); Owner Builder (56 in ½ mi · Remodel / interior alteration); Owner (39 in ½ mi · Remodel / interior alteration); Hendrickson Pools (12 in ½ mi · Pool / spa).
Permit & Project History on This Parcel (3 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 173849 | Remodel / interior alteration | Issued | Iss. Apr 20, 2023 | $161,000 | Structural Kitchen Remodel |
| 171715 | Remodel / interior alteration | Issued | Iss. Jun 17, 2022 | $6,800 | Bath Remodel - Express |
| 145452 | Remodel / interior alteration | Issued | Iss. Jan 14, 2015 | $90,000 | Nonstruct. Bath Rmdl-Express |