According to this map, 49% of Berkeley residential areas are single-family zoned: https://www.berkeleyside.com/2021/02/17/berkeley-may-get-rid-of-single-family

According to this map, 49% of Berkeley residential areas are single-family zoned: https://www.berkeleyside.com/2021/02/17/berkeley-may-get-rid-of-single-family-zoning-as-a-way-to-correct-the-arc-of-its-ugly-housing-history https://www.berkeleyside.com/2021/02/17/berkeley-may-get-rid... But yeah I think in practice the bigger question is whether Berkeley will streamline the process for replacing single-family houses with apartment buildings. AFAICT that is technically permitted but the approval process rejects the vast majority of applications.