1123 A W California Ave
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.88901, -122.54237
Parcel & Assessor
- Lot size:
- 6,795 sq ft (0.16 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 1123A W CALIFORNIA AVE; 1123 W CALIFORNIA 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 6,795 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
- High 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 06041C0468F, 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: $2,058,000 – $2,620,000 · Status: Off market
HUD Small Area FMR (ZIP 94941) · FY 2026
Studio $2,730 · 1BR $3,270 · 2BR $3,960 · 3BR $5,060 · 4BR $5,240
Developments Deserving Closer Investigation & Active Area Builders
- Accessory dwelling unit at 1123 W California Ave (adu 1123a) (Issued)On this parcel
Active in "Issued" for 2.1 yr (first record Oct 7, 2024) with no new permit activity recorded in 20 mo.
- New home at 560 Alta Way (Applied)0.26 mi S
Active in "Applied" for 3.2 yr (first record Aug 10, 2023) with no new permit activity recorded in 3.2 yr. High-impact scale (1 housing unit, $975,000 declared valuation across 1 permit).
- New home at 210 Brabo Ter (Issued)0.29 mi N
Active in "Issued" for 3 yr (first record Oct 12, 2023) with no new permit activity recorded in 2.6 yr. High-impact scale (1 housing unit, $850,000 declared valuation across 1 permit).
- New home at 204 Reed St (Issued)0.32 mi N
Active in "Issued" for 4.2 yr (first record Aug 5, 2022) with no new permit activity recorded in 3.5 yr. High-impact scale (1 housing unit, $950,000 declared valuation across 1 permit).
Permit & Project History on This Parcel (2 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B42644 | Roof replacement | Issued | Iss. Jun 4, 2025 | $10,400 | Remove existing roof. Install with new Lifetime Class A composition shingles.Lower section of main house. — ReRoofing |
| 178793 | Accessory dwelling unit (new or conversion) | Issued | Iss. Mar 7, 2025 | $150,000 | Expand Garage And Convert Portion To A D U |
State HCD Housing Element APR records on this parcel: 1 entry (report years 2025).