The lack of affordable housing in the US right now is worse than ever, largely due to the lack of available housing. By looking at a map of zoning regulations in the Bay Area, it is clear what is driving the shortage. The areas shaded in pink are restricted to single-family housing only, making up 82% of all residential land. Additionally, many places have height restrictions, such as Cupertino, California, where multi-family buildings are only allowed to be two stories high. Parking requirements are also often written into zoning laws, with Cupertino requiring two parking spaces for each unit of multi-family housing. Minimum lot sizes are also a feature of many zoning laws, with Cupertino requiring single-family lots to be at least 5000 square feet each. These exclusionary zoning laws cause builders across the country to focus on bigger luxury homes instead of smaller starter homes or multi-family housing.