150 W Oak Knoll Dr
San Anselmo 94960 · Sleepy Hollow · Unincorporated Marin · Coordinates: 38.00198, -122.58190
Executive Verdict · Public-Records Synthesis
Zoned RMP-0.2 in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE moderate fire hazard severity zone (state responsibility area) due diligence; benchmark value $1,880,000 ($1,654,000–$2,106,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-0.2 allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$87,600 contributory est.)
Public building records show issued construction/renovation work on this parcel (5 total permits, latest Nov 11, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Sleepy Hollow
32 substantial renovation & housing permits over 24 months (32.7 per 1,000 parcels vs. 16.3 citywide baseline) (#4 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Sleepy Hollow)
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)
- ! CAL FIRE Moderate Fire Hazard Severity Zone (State Responsibility Area) (all of the lot of lot)
Located in a mapped Fire Hazard Severity Zone. Expect Chapter 7A ignition-resistant building standards, defensible-space inspections, and stricter property insurance underwriting.
Source: CAL FIRE FHSZ (map Apr 1, 2024)
- ! Delayed or open permit activity on this parcel
Addition (adds square footage) (154270): Issued after 11 mo (2.1× the 160d median) — above the 75th percentile for addition (adds square footage) permits in Unincorporated Marin (median 160d, 75th pct 249d, n=316).
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 40 De Burgh Dr (0.37 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)
Parcel & Assessor
- Lot size:
- 142,964 sq ft (3.28 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 150 W OAK KNOLL DR
Zoning & Land Use
RMP-0.2 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-0.2 (multifamily residential): state law allows ADUs where homes are allowed. On a multifamily lot the state allowance is different: ADUs in non-living space of the building, plus up to eight detached ADUs.
- SB 9: two homes on the lotUnlikely
Zoned RMP-0.2 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-0.2 (multifamily residential), not a single-family residential zone.
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 06041C0289D, effective May 4, 2009
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,654,000 – $2,106,000 · Status: Off market
HUD Small Area FMR (ZIP 94960) · FY 2026
Studio $2,510 · 1BR $3,010 · 2BR $3,640 · 3BR $4,650 · 4BR $4,820
Nearby Activity (½ mile radius, since November 2024)
3 active or recent development projects (3 housing units across completed, permitted, and pipeline stages) and 149 total building permits recorded within ½ mile.
- New construction2 permits
- Adds housing (ADU)1 permit (1 units)
- Additions & renovations10 permits
- Building systems104 permits
- Repairs11 permits
- Other21 permits
Developments Deserving Closer Investigation & Active Area Builders
- New home at 40 De Burgh Dr (Applied)0.37 mi N
In "Applied" for 9.3 yr (since Jul 31, 2017), 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, $1,800,000 declared valuation across 3 permits).
- New home at 830 Butterfield Rd (Issued)0.42 mi E
Active in "Issued" for 8.3 yr (first record Aug 9, 2018) with no new permit activity recorded in 7.6 yr. High-impact scale (1 housing unit, $1,097,000 declared valuation across 2 permits).
- New home at 71 W Oak Knoll Dr (Applied)480 ft SW
In "Applied" for 5.2 yr (since Sep 1, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- Addition (adds square footage) (154270) (Issued)On this parcel
Issued after 11 mo (2.1× the 160d median) — above the 75th percentile for addition (adds square footage) permits in Unincorporated Marin (median 160d, 75th pct 249d, n=316).
Entity-resolved builders & contractors in ½ mile: Owner (3 on parcel, 12 in ½ mi · Remodel / interior alteration); Apollo Building And Roofing Group (1 on parcel, 1 in ½ mi · Roof replacement); Ernest Ongaro And Sons (1 on parcel, 1 in ½ mi · Electrical / panel); Owner Builder (27 in ½ mi · Remodel / interior alteration); First Impressions Painting And Building (4 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (5 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B49088 | Roof replacement | Issued | Iss. Nov 11, 2026 | $75,000 | ReRoofing |
| B48927 | Electrical / panel | Issued | Iss. Oct 28, 2026 | $25,000 | Replace Circuits / Outlets |
| 154270 | Addition (adds square footage) | Issued | Iss. Jan 4, 2017 | $160,000 | Acc Struct W/Deck - Det, B W O P T.D. 03/10/16 |
| 151315 | Solar / battery storage | Issued | Iss. Mar 24, 2016 | $60,000 | P V 15.6kw Ground Mount |
| 151314 | Electrical / panel | Issued | Iss. Mar 24, 2016 | $4,500 | Panel Upgr To 400 A; Split In (2) 200 A Breakers, 1 For Solar & 1 For House, Incl New Breakers & A C Disconnect |