538 Northern Ave
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.88167, -122.54152
Parcel & Assessor
- Lot size:
- 17,729 sq ft (0.41 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 538 NORTHERN AVE
Zoning & Land Use
RA-B2 — Residential Agriculture (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RA-B2 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotCan't tell
Zoned RA-B2 (single-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential agriculture, estate and restricted: large-lot residential; confirm SB 9 with the county.
- SB 9: split into two lotsCan't tell
Zoned RA-B2 (single-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential agriculture, estate and restricted: large-lot residential; confirm SB 9 with the county.
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 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: $1,978,000 – $2,518,000 · 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
- New home at 538 Northern Ave (Issued)On this parcel
Active in "Issued" for 12.1 yr (first record Sep 29, 2014) with no new permit activity recorded in 11.3 yr.
- New home at 731 Bay Rd (Issued)0.21 mi S
Active in "Issued" for 18 mo (first record May 12, 2025) with no new permit activity recorded in 14 mo. High-impact scale (1 housing unit, $955,000 declared valuation across 1 permit).
- New home at 560 Alta Way (Applied)0.27 mi N
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 407 Spruce St (Issued)0.35 mi SE
Active in "Issued" for 7.6 yr (first record Mar 14, 2019) with no new permit activity recorded in 7.4 yr. High-impact scale (1 housing unit, $750,000 declared valuation across 1 permit).
Permit & Project History on This Parcel (3 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B37676 | HVAC / heat pump | Issued | Iss. Apr 16, 2024 | $15,500 | Replace failed furnace with new furnace and install AC new — Replace Mechanical Appliance |
| 148130 | New single-family home | Issued | Iss. Jul 27, 2015 | $600,000 | Demo & Rebuild Single Family Residence T.D. 11/28/14 |
| 148104 | Electrical / panel | Issued | Iss. Jul 22, 2015 | $200 | Temporary Power Pole |