Discover the hidden potential for infill housing on lots in California
Recent California laws have made it faster, cheaper, and more predictable to build new homes on existing lots in places you want to live, work, and grow.
Infillworks is a free and open resource to help you see what’s possible.
Currently serving parts of the Bay Area and expanding slowly.
Explore local listings
Explore active listings or look up a residential property
Browse homes currently on the market or search any residential address to see what's there today — and what it could become.
Explore potential infill development scenarios
See development scenarios generated from real site conditions — lot size, zoning, setbacks, and the laws that apply.
Understand costs and timelines
Get a grounded picture of what it takes to build, from estimated costs to permitting and construction timelines.
The laws making missing middle housing possible in California
A new wave of state housing laws is quietly unlocking more homes on lots across the state.
SB 9
What SB-9's "lot splits" mean for homeowners in California
Read the overview
SB 684
What SB-684's ministerial pathway means for small-scale housing in California
Read the overview
SB 1123
How SB-1123 fills the gaps left by California's starter home law
Read the overview
AB 1033
What condo-ization means for ADUs and for California homeowners.
Read the overview
ADU Laws
What California's ADU's framework means for homeowners across the state
Read the overview