53 S Knoll Rd
Mill Valley 94941 · Strawberry · Unincorporated Marin · Coordinates: 37.90071, -122.51169
Executive Verdict · Public-Records Synthesis
Zoned RA-B2 in Unincorporated Marin with likely ministerial ADU eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,335,000 ($2,055,000–$2,615,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RA-B2 allows residential use qualifying for ministerial ADU review under state law (7 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$11,109 contributory est.)
Public building records show issued construction/renovation work on this parcel (2 total permits, latest Sep 30, 2022).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Strawberry
43 substantial renovation & housing permits over 24 months (28.4 per 1,000 parcels vs. 16.4 citywide baseline) (#1 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Strawberry)
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 at 53 S Knoll Rd: Active in "Issued" for 6.6 yr (first record Apr 7, 2020) with no new permit activity recorded in 6 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 55 Thomas Dr (0.34 mi N, applied). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
- ! Year 1 Prop 13 tax reset (~$27,303/yr at $2,335,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,275/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 19,036 sq ft (0.44 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 53 S KNOLL RD
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
- 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 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: $2,055,000 – $2,615,000 · 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 53 S Knoll Rd (Issued)On this parcel
Active in "Issued" for 6.6 yr (first record Apr 7, 2020) with no new permit activity recorded in 6 yr.
- New home at 55 Thomas Dr (Applied)0.34 mi N
In "Applied" for 6.2 yr (since Sep 1, 2020), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121). High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
- New home at 55 S Knoll Rd (Issued)60 ft E
Active in "Issued" for 11.9 yr (first record Dec 22, 2014) with no new permit activity recorded in 11.4 yr. High-impact scale (1 housing unit, $750,000 declared valuation across 1 permit).
- New home at 9 Sky Rd (Issued)0.27 mi E
Active in "Issued" for 12.4 yr (first record Jun 23, 2014) with no new permit activity recorded in 11.6 yr. High-impact scale (1 housing unit, $1,200,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Argo Construction (1 on parcel, 2 in ½ mi · New garage / accessory structure); Tesla Energy Operations (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner Builder (66 in ½ mi · Remodel / interior alteration); Owner (35 in ½ mi · Remodel / interior alteration); Juan Calmell (8 in ½ mi · Demolition).
Permit & Project History on This Parcel (2 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B31245 | Solar / battery storage | Issued | Iss. Sep 30, 2022 | $29,390 | Install (26) roof mount solar panels at 10.4 kW and 2 batteries |
| 166138 | New single-family home | Issued | Iss. Nov 3, 2020 | $500,000 | T/Dwn & Rebuild Home T.D. 6/1/20 |
State HCD Housing Element APR records on this parcel: 1 entry (report years 2020).