2431 San Carlos Ave
Castro Valley 94546 · Castro Valley · Unincorporated Alameda County · Coordinates: 37.69371, -122.09240
Parcel & Assessor
- Lot size:
- 21,994 sq ft (0.50 ac)
- Assessor use:
- 2 units, SFR with attached accessory dwelling unit
- Tax rate area:
- 54
- Addresses on lot:
- 2431 SAN CARLOS AVE
Zoning & Land Use
No published city zoning district at parcel centroid.
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADUCan't tell
We don't have a zoning map for Unincorporated Alameda County.
- SB 9: two homes on the lotCan't tell
We don't have a zoning map for Unincorporated Alameda County.
- SB 9: split into two lotsCan't tell
We don't have a zoning map for Unincorporated Alameda 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 06001C0279G, effective August 3, 2009
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,116,000 – $1,420,000 · Status: Off market
HUD Small Area FMR (ZIP 94546) · FY 2026
Studio $2,210 · 1BR $2,460 · 2BR $3,000 · 3BR $3,840 · 4BR $4,550
Nearby Activity (½ mile radius, since —)
2 active or recent development projects (2 housing units across completed, permitted, and pipeline stages) and 0 total building permits recorded within ½ mile.
Developments Deserving Closer Investigation & Active Area Builders
- New home (Issued)On this parcel
Active in "Issued" for 3.4 yr (first record Jun 15, 2023) with no new permit activity recorded in 3.4 yr.
- New home (Issued)0.13 mi NE
Active in "Issued" for 2.5 yr (first record May 17, 2024) with no new permit activity recorded in 2.5 yr.
- New home (Issued)0.22 mi N
Active in "Issued" for 4 yr (first record Nov 1, 2022) with no new permit activity recorded in 4 yr.
- New home (Issued)0.23 mi W
Active in "Issued" for 17 mo (first record May 29, 2025) with no new permit activity recorded in 17 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: 1 entry (report years 2023).