SB 9 Lot Split Feasibility Screener
Senate Bill 9 allows homeowners and developers to bypass local zoning and split single-family lots or build duplexes by-right. Use our screener to find active Silicon Valley listings that meet the state's stringent eligibility criteria.
Urban Footprint
Properties must be located within a designated urbanized area or urban cluster to qualify for SB 9.
Hazard Zones
We automatically filter out properties in very high fire hazard severity zones and active earthquake fault zones.
Lot Size Minimums
Adjust the minimum lot size filter below to ensure the resulting split parcels meet the 1,200 sqft minimum.
Active SB9 Eligible Listings
Filters
Zoning & Risk
$4,680,000
510 Woodside Dr, Woodside
$1,325,000
16 Clarence Ct, East Palo Alto
$2,950,000
40 Powhatan Pl, San Mateo
$2,400,000
1708 Monticello Rd, San Mateo
$2,998,000
2611 Barclay Way, Belmont
$1,899,000
1981 Johnston Ave, San Jose
$1,888,000
2663 LA Salle Way, San Jose
$2,799,000
1169 Ramblewood Way, San Mateo
This eligibility check runs on the AddressIntel data platform: the same daily-refreshed parcel, zoning, and hazard-overlay records that also drive our ADU feasibility and teardown and underbuilt-lot screeners. For pipeline-scale sourcing beyond this page, the same signals are available through a monthly Developer Market Opportunities Report and a REST API.
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SB 9 Lot Split FAQ
What makes a property eligible for an SB 9 lot split?
SB 9 lets you bypass local zoning to split a single-family lot or build a duplex by-right, but the property must sit within a designated urbanized area or urban cluster, stay out of very high fire hazard severity zones and active earthquake fault zones, and be large enough that the resulting parcels meet the 1,200 square foot minimum.
Can an SB 9 lot split happen in a fire hazard zone?
No. The screener automatically filters out properties in very high fire hazard severity zones and active earthquake fault zones, which disqualify a parcel from SB 9. This is a major reason so many otherwise attractive Peninsula lots fail eligibility.
How big does my lot need to be for an SB 9 split?
Each resulting parcel must meet the 1,200 square foot minimum after the split. To keep results realistically viable, this screener therefore defaults to a 3,000 square foot minimum lot size, you can raise the minimum lot size filter to be more conservative.
How many units does SB 9 allow?
SB 9 lets homeowners and developers split a single-family lot in two and build duplexes by-right, opening the door to multiple units where local zoning previously allowed only one home.
Which markets does this SB 9 screener cover?
The screener surfaces active real estate listings across San Mateo County and Santa Clara County, scored against SB 9 eligibility criteria so you can focus on Silicon Valley lots that can actually be split or converted.
Is this SB 9 screener part of a larger platform?
Yes. It is one screener inside AddressIntel, a real estate data platform built for Silicon Valley developers, spec builders, and investors. The same parcel, permit, and hazard data also powers our ADU-feasibility and teardown/underbuilt-lot screeners, so a listing’s SB 9, ADU, and teardown signals all live together on its detail page. Beyond this page, the data is available through a monthly Developer Market Opportunities Report and a REST API.
See every signal on one lot
AddressIntel scores every Silicon Valley listing for SB 9, ADU, and teardown upside side by side, plus off-market candidates that never make it to MLS.
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