311 Summit Ave
San Rafael 94901 · Country Club · Unincorporated Marin · Coordinates: 37.97524, -122.50533
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 $1,765,000 ($1,553,000–$1,977,000).
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 64,687 sq ft lot. Local precedent is active with 4 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$30,600 contributory est.)
Public building records show issued construction/renovation work on this parcel (6 total permits, latest Oct 20, 2021).
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
New garage / accessory structure (87941): Pending in review for 5.6 yr (12.5× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 4 slow or stalled nearby projects within ½ mile
Closest lead: New home (0.47 mi W, 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:
- 64,687 sq ft (1.49 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 311 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 64,687 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: $1,553,000 – $1,977,000 · 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)0.47 mi W
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).
- New garage / accessory structure (87941) (Applied)On this parcel
Pending in review for 5.6 yr (12.5× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
- Remodel / interior alteration (71448) (Applied)On this parcel
Pending in review for 12.3 yr (54.1× the 83d median) — slower than 90% of remodel / interior alteration permits in Unincorporated Marin (median 83d, 90th pct 266d, n=1,054).
- New home at 195 Fairway Dr (Issued)0.13 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).
Entity-resolved builders & contractors in ½ mile: S And S Landscaping (2 on parcel, 2 in ½ mi · General repair); Bellows Plumbing Heating And Air (1 on parcel, 1 in ½ mi · HVAC / heat pump); United Vi Plumbing (1 on parcel, 1 in ½ mi · Plumbing / water heater / sewer); Owner Builder (26 in ½ mi · Remodel / interior alteration); Owner (19 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (6 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B27488 | HVAC / heat pump | Issued | Iss. Oct 20, 2021 | $3,500 | Replace existing 80% furnace in utility room with new 96% furnace, like for like. — Replace Mechanical Appliance |
| 87941 | New garage / accessory structure | Applied | App. Apr 9, 2021 | $150,000 | Deck, Storage Under Deck, Covered Patio Siding, Fire Pit, Bbq Area, Electrical |
| 158439 | General repair | Issued | Iss. May 9, 2018 | $150,000 | Retaining Walls***Expired |
| 158438 | Pool / spa | Issued | Iss. May 9, 2018 | $100,000 | New Pool***Expired T.D. 3/22/18 |
| B11081 | Plumbing / water heater / sewer | Issued | Iss. Sep 26, 2016 |