408 Spruce St
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.87893, -122.53662
Parcel & Assessor
- Lot size:
- 15,377 sq ft (0.35 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 408 SPRUCE ST; 410 SPRUCE ST
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 15,377 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 (Local Responsibility Area) (all of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone X: 0.2% annual chance flood hazard (shaded X) (about 14% of the lot); Zone X: minimal flood hazard (about 86% 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)
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 410 Spruce St (aka 408) (Issued)On this parcel
Active in "Issued" for 4.3 yr (first record Jul 4, 2022) with no new permit activity recorded in 3.6 yr.
- Accessory dwelling unit at 403 Marin Ave (adu 403a) (Issued)430 ft SE
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).
- New home at 731 Bay Rd (Issued)0.22 mi W
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 469 W Live Oak Dr (aka 461) (Issued)0.25 mi SW
Active in "Issued" for 6 yr (first record Oct 22, 2020) with no new permit activity recorded in 21 mo. High-impact scale (1 housing unit, $980,000 declared valuation across 1 permit).
Permit & Project History on This Parcel (9 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 173518 | Accessory dwelling unit (new or conversion) | Issued | Iss. Mar 7, 2023 | $40,000 | Factory-Built A D U |
| B30261 | Electrical / panel | Issued | Iss. Jul 1, 2022 | $83,131 | service upgrade — Service Upgrade |
| B28148 | Solar / battery storage | Issued | Iss. Dec 22, 2021 | $92,466 | installation of 49 panels (17.885kW) on roof for solar PV system with main panel upgrade |
| 169064 | Solar / battery storage | Issued | Iss. Aug 10, 2021 | $92,466 | 17.88kw Rooftop Photovoltaic And Energy Storage System |