456 Ethel Ave
Mill Valley 94941 · Mill Valley · Coordinates: 37.89843, -122.53942
Executive Verdict · Public-Records Synthesis
Zoned RS-6 in Mill Valley with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,091,000 ($1,777,000–$2,405,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned RS-6 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 3,572 sq ft lot.
Source: Mill Valley zoning · CA Gov. Code 66314 & 65852.21
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)
- ! Delayed or open permit activity on this parcel
New home: Active in "Entitled" for 8 yr (first record Nov 27, 2018) with no new permit activity recorded in 8 yr.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 5 slow or stalled nearby projects within ½ mile
Closest lead: New home at 107 Montford Ave (0.16 mi SW, issued). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
- ! Bulk building permits not published for Mill Valley
Permit counts and nearby activity on this page may omit municipal counter records. Request a parcel permit report directly from the local building department.
Source: Source coverage registry (Mill Valley)
Parcel & Assessor
- Lot size:
- 3,572 sq ft (0.08 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 456 ETHEL AVE
Zoning & Land Use
RS-6 — Single Fam Res (min 6,000 SF) (Mill Valley)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RS-6 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned RS-6, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned RS-6, a single-family residential zone. The lot is 3,572 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
- Not in a State-mapped fire hazard severity zone
- 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: $1,777,000 – $2,405,000 · 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
Nearby Activity (½ mile radius, since November 2024)
25 active or recent development projects (23 housing units across completed, permitted, and pipeline stages) and 218 total building permits recorded within ½ mile.
Developments Deserving Closer Investigation & Active Area Builders
- New home (Entitled)On this parcel
Active in "Entitled" for 8 yr (first record Nov 27, 2018) with no new permit activity recorded in 8 yr.
- New home at 107 Montford Ave (Issued)0.16 mi SW
Active in "Issued" for 3.9 yr (first record Dec 15, 2022) with no new permit activity recorded in 2.5 yr. High-impact scale (1 housing unit, $1,375,000 declared valuation across 1 permit).
- New home at 204 Reed St (Issued)0.35 mi S
Active in "Issued" for 4.3 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).
- New home at 210 Brabo Ter (Issued)0.38 mi S
Active in "Issued" for 3.1 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).
Permit & Project History on This Parcel (0 permits, 1 grouped projects)
No building permits recorded on this parcel in our dataset.
State HCD Housing Element APR records on this parcel: 1 entry (report years 2018).