Zoning Considerations When Building Granny Flats
"More homeowners are looking at mother-in-law apartments as a way to accommodate the needs of extended family or generate extra income. In-law units are desirable in many urban markets because they create affordable housing for renters, extra income for homeowners who want mortgage help, or long-term guest suites that allow owners with far-flung friends and family to have privacy during visits... City and county attitudes about accessory apartments vary widely throughout the country. Most define accessory units as spaces that include their own entrance, plumbing, kitchens and square footage similar to a studio apartment or apartment. Some municipalities, in an effort to foster affordable housing or prevent sprawl, have loosened regulations on mother-in-law units."
Thanks to Chris Steins