319 A Ross Dr
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.87749, -122.52948
Parcel & Assessor
- Lot size:
- 7,710 sq ft (0.18 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 319A ROSS DR; 319 ROSS DR
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 lotPossible, with conditions
Zoned R1, a single-family residential zone. FEMA regulatory floodway covers all of the lot: SB 9 requires a no-rise certification.
- SB 9: split into two lotsPossible, with conditions
Zoned R1, a single-family residential zone. The lot is 7,710 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. FEMA regulatory floodway covers all of the lot: SB 9 requires a no-rise certification.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Moderate Fire Hazard Severity Zone (Local Responsibility Area) (about 34% of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone AE: regulatory floodway (Special Flood Hazard Area) (all of the lot) · FIRM panel 06041C0469F, 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: $1,857,000 – $2,363,000 · 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 319 Ross Dr (Applied)On this parcel
Active in "Applied" for 17 mo (first record Jun 13, 2025) with no new permit activity recorded in 17 mo.
- New home at 334 Dolan Ave (Issued)0.25 mi N
Active in "Issued" for 8.2 yr (first record Sep 5, 2018) with no new permit activity recorded in 7.9 yr. High-impact scale (1 housing unit, $759,000 declared valuation across 1 permit).
- New commercial building at 201 Flamingo Rd (aka 205) (Issued)0.3 mi NE
Active in "Issued" for 11.7 yr (first record Feb 17, 2015) with no new permit activity recorded in 11.2 yr. High-impact scale ($3,938,400 declared valuation across 3 permits).
- Accessory dwelling unit at 403 Marin Ave (adu 403a) (Issued)0.34 mi W
Active in "Issued" for 2.9 yr (first record Dec 21, 2023) with no new permit activity recorded in 18 mo. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
Permit & Project History on This Parcel (4 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B46785 | Roof replacement | Issued | Iss. May 13, 2026 | $18,220 | ReRoofing |
| 93632 | Remodel / interior alteration | Applied | App. Oct 16, 2025 | — | Convert Part Of Garage To Family Rm W/ Bay Window; Skylight In Laundry |
| 93272 | Accessory dwelling unit (new or conversion) | Applied | App. Jun 13, 2025 | $210,000 | New Attached A D U; Convert Partial Garage To A D U Kitchen; Converte Partial Garage To (N) Family Rm W/ Bay Window |
| B24865 | HVAC / heat pump | Issued | Iss. Feb 11, 2021 | $7,250 |