313 Summit Ave
San Rafael 94901 · Country Club · Unincorporated Marin · Coordinates: 37.97598, -122.50527
Executive Verdict · Public-Records Synthesis
Zoned R1-B4 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE moderate fire hazard severity zone (local responsibility area) due diligence; benchmark value $1,734,000 ($1,526,000–$1,942,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1-B4 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 59,939 sq ft lot. Local precedent is active with 5 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ 6 documented municipal building permits on file
On-parcel permit history is indexed through Apr 4, 2024, letting you verify roof, HVAC, electrical, or structural work against seller disclosures.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
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 (Local 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 Mar 24, 2025)
- ! Delayed or open permit activity on this parcel
General repair (91334): Pending in review for 3.3 yr (14.6× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
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 (0.49 mi SW, entitled). 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:
- 59,939 sq ft (1.38 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 313 SUMMIT AVE
Zoning & Land Use
R1-B4 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B4 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-B4, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B4, a single-family residential zone. The lot is 59,939 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
- Moderate Fire Hazard Severity Zone (Local Responsibility Area) (all of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0457E, 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: $1,526,000 – $1,942,000 · Status: Off market
HUD Small Area FMR (ZIP 94901) · FY 2026
Studio $2,150 · 1BR $2,580 · 2BR $3,120 · 3BR $3,990 · 4BR $4,130
Developments Deserving Closer Investigation & Active Area Builders
- New home (Entitled)0.49 mi SW
In "Entitled" for 7 yr (since Nov 26, 2019), 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 deed-restricted affordable across 0 permits).
- General repair (91334) (Applied)On this parcel
Pending in review for 3.3 yr (14.6× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
- New home at 195 Fairway Dr (Issued)0.12 mi E
Active in "Issued" for 5.6 yr (first record Mar 22, 2021) with no new permit activity recorded in 5.5 yr. High-impact scale (1 housing unit, $1,400,000 declared valuation across 1 permit).
- New home at 195 Fairway Dr (Issued)0.12 mi E
Active in "Issued" for 12.9 yr (first record Dec 26, 2013) with no new permit activity recorded in 10.4 yr. High-impact scale (1 housing unit, $1,636,842 declared valuation across 2 permits).
Entity-resolved builders & contractors in ½ mile: Rca Electric (2 on parcel, 2 in ½ mi · Electrical / panel); Bay Area Window Pros (1 on parcel, 1 in ½ mi · Windows / doors / siding); Richard Osorio Heating And Air (1 on parcel, 1 in ½ mi · HVAC / heat pump); Nigel Mulgrew Plumbing (1 on parcel, 1 in ½ mi · Plumbing / water heater / sewer); Owner Builder (25 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (6 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B37566 | Windows / doors / siding | Issued | Iss. Apr 4, 2024 | $49,600 | Replace 10(E) windows. Same size and location. — Non-structural Door/Window Replacement |
| B36239 | HVAC / heat pump | Issued | Iss. Nov 28, 2023 | $23,000 | Install furnace in new location with duct work, (ATTIC) — New Ductwork, Mechanical Appliance |
| 91334 | General repair | Applied | App. Jul 18, 2023 | $250,000 | Replace (E) Wood Retaining Wall W/ (N) Concrete Wall @ East Side Of Driveway; Free Standing Walls & Gates @ Entry |
| B33374 | Plumbing / water heater / sewer | Issued | Iss. Apr 11, 2023 | $10,000 | New 2 water service — Replace Plumbing Fixtures(s) |
| B33366 | Electrical / panel |