California passes a law that ended exclusive single-family home zoning in transit-rich and urban infill areas throughout the state. Until this law, it was illegal for property owners and builders to construct duplexes, triplexes, multifamily units or any other housing types on lots in areas zoned as single-family. Experts expect the impact of the new law will take time, but it signals a major step forward in making additional properties available for new-construction units, and a cultural shift toward encouraging increased housing density.