21 Tamal Vista Ln
Greenbrae 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.95786, -122.53152
Executive Verdict · Public-Records Synthesis
Zoned RSP-0.33 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE moderate fire hazard severity zone (local responsibility area) due diligence; benchmark value $2,216,000 ($1,950,000–$2,482,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned RSP-0.33 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 192,100 sq ft lot. Local precedent is active with 4 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ 3 documented municipal building permits on file
On-parcel permit history is indexed through Jun 16, 2023, letting you verify roof, HVAC, electrical, or structural work against seller disclosures.
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)
- ! Delayed or open permit activity on this parcel
Other (89063): Pending in review for 5.1 yr — slower than 90% of other permits in Unincorporated Marin (median 0d, 90th pct 71d, n=1,560).
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: Accessory dwelling unit at 34 Wolfe Grade (0.32 mi 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:
- 192,100 sq ft (4.41 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 21 TAMAL VISTA LN
Zoning & Land Use
RSP-0.33 — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RSP-0.33 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned RSP-0.33, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned RSP-0.33, a single-family residential zone. The lot is 192,100 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 (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: $1,950,000 – $2,482,000 · 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 34 Wolfe Grade (Applied)0.32 mi SW
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).
- Other (89063) (Applied)On this parcel
Pending in review for 5.1 yr — slower than 90% of other permits in Unincorporated Marin (median 0d, 90th pct 71d, n=1,560).
- New home at 138 Cypress Ave (Issued)0.32 mi W
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 29 Mann Dr (Issued)0.39 mi W
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: Pacific Ridge Construction (1 on parcel, 1 in ½ mi · New garage / accessory structure); Millsap Degnan And Associates (1 on parcel, 1 in ½ mi · General repair); Owner Builder (38 in ½ mi · Remodel / interior alteration); Owner (23 in ½ mi · Remodel / interior alteration); Hendrickson Pools (9 in ½ mi · Pool / spa).
Permit & Project History on This Parcel (3 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 174312 | General repair | Issued | Iss. Jun 16, 2023 | $100,000 | Retaining Wall System & New Drainage - Emergency Mudslide Repairs |
| 89063 | Other | Applied | App. Oct 12, 2021 | — | Design Change For #168841 - All Work In Master Bedroom Des Chg Listed In 168841. This Record 86'd |
| 168841 | New garage / accessory structure | Issued | Iss. Aug 20, 2021 | $275,000 | Small Addition; Reconfig Bedrm Wing To Make Master Suite, 2 Additional Bdrms & Bath; Stairs To Bsmt |