B
erkeley is offering a four-year amnesty program to single-family homeowners who built unpermitted accessory dwelling units, also known as granny flats. The program allows these homeowners to legalize their previously undocumented apartments without facing penalties. The affected ADUs range from converted basements and garages to in-law garden units.

    Homeowners can approach city planners to have their unpermitted units inspected for safety and then legalized through a confidential process. A Berkeley planning report estimates that there may be as many as 4,000 illegal units in the city. The amnesty program aims to encourage homeowners who are nervous about coming forward to "come out of the shadows."

    The ADUs are among the most affordable housing options in Berkeley, where typical home values are nearly $1.3 million and average rent is nearly $2,700. Some landlords had left their unpermitted ADUs vacant due to concerns over liability risk or getting slapped with a notice of violation.

    To participate in the amnesty program, homeowners can either obtain a certificate of occupancy by following the standard building permit process or a certificate of compliance by demonstrating that their unit meets housing code and minimum fire and life safety standards. The less rigorous "certificate of compliance" option was made possible by a bill pushed by the Casita Coalition in 2023.

    Berkeley's amnesty program comes as California works to make it easier and cheaper to build ADUs, with more than 80,000 permitted since the first reform bill was passed in 2016. The state has also designated Berkeley as one of six "prohousing" cities in Northern California.