100 Upper Briar Rd
Kentfield 94904 · Kentfield · Unincorporated Marin · Coordinates: 37.94342, -122.54987
Executive Verdict · Public-Records Synthesis
Zoned R1 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 $2,380,000 ($2,094,000–$2,666,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 8,625 sq ft lot.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$99,840 contributory est.)
Public building records show issued construction/renovation work on this parcel (4 total permits, latest Sep 8, 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)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: Magnolia Village (0.37 mi NE, 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 (~$27,820/yr at $2,380,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,318/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:
- 8,625 sq ft (0.20 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 100 UPPER BRIAR RD
Zoning & Land Use
R1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1, a single-family residential zone. The lot is 8,625 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: $2,094,000 – $2,666,000 · 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)0.37 mi NE
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 home at 100 Black Log Rd (Applied)0.16 mi S
In "Applied" for 10.7 yr (since Feb 22, 2016), 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, $1,400,000 declared valuation across 1 permit).
- New home at 70 Ridgecrest Rd (Issued)0.36 mi SW
Active in "Issued" for 8.4 yr (first record Jun 28, 2018) with no new permit activity recorded in 7.4 yr. High-impact scale (1 housing unit, $2,500,000 declared valuation across 1 permit).
- Demolition at 15 Blue Ridge Rd (Issued)0.37 mi SW
Active in "Issued" for 3.1 yr (first record Oct 13, 2023) with no new permit activity recorded in 2.9 yr. High-impact scale ($871,339 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Owner (1 on parcel, 7 in ½ mi · Remodel / interior alteration); Reyes Heating And Air (1 on parcel, 1 in ½ mi · HVAC / heat pump); Mc Leran (1 on parcel, 1 in ½ mi · Roof replacement); Ongaro Ernest And Sons (1 on parcel, 1 in ½ mi · HVAC / heat pump); Owner Builder (32 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B43775 | HVAC / heat pump | Issued | Iss. Sep 8, 2025 | $22,000 | Add Mitsubishi heat pump A/C model # 5A6H50601000A and mini split system Model # MXZ-3D24NL. Two wall mounted units mode… |
| B37455 | Roof replacement | Issued | Iss. Mar 25, 2024 | $15,800 | Tear off lower middle sloped section of the main roof to solid sheeting. Re-roof with Class A Lifetime Shingles. — ReRoo… |
| 155784 | Addition (adds square footage) | Issued | Iss. Jun 20, 2017 | $208,000 | Rmdl, Addn, Deck Repairs T.D. 4/18/17 |
| 150284 | HVAC / heat pump | Issued | Iss. Dec 31, 2015 | $4,200 | Rplc Furnace***Expired |