20 Carlson Ave
San Anselmo 94960 · San Anselmo · Coordinates: 37.99357, -122.57745
Parcel & Assessor
- Lot size:
- 5,314 sq ft (0.12 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 20 CARLSON AVE
Zoning & Land Use
R-1 — Single Family Residential (San Anselmo)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R-1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R-1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R-1, a single-family residential zone. The lot is 5,314 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) (about 5% of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0452E, effective March 17, 2014
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,433,000 – $1,939,000 · 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 October 2024)
11 active or recent development projects (11 housing units across completed, permitted, and pipeline stages) and 17 total building permits recorded within ½ mile.
- Adds housing (ADU)1 permit (1 units)
Developments Deserving Closer Investigation & Active Area Builders
- New home at 116 Holstein Rd (Issued)0.38 mi NE
Active in "Issued" for 12.8 yr (first record Dec 24, 2013) with no new permit activity recorded in 12.4 yr. High-impact scale (1 housing unit, $800,000 declared valuation across 1 permit).
- New home (Issued)500 ft W
Active in "Issued" for 5.1 yr (first record Oct 5, 2021) with no new permit activity recorded in 5.1 yr.
- New home (Entitled)500 ft W
Active in "Entitled" for 6.6 yr (first record Mar 8, 2020) with no new permit activity recorded in 6.6 yr.
- New home (Issued)0.13 mi E
Active in "Issued" for 20 mo (first record Mar 3, 2025) with no new permit activity recorded in 20 mo.
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: 2 entries (report years 2024, 2025).