12-20 Santa Rosa Ave, San Francisco, CA 94112

The 12-20 Santa Rosa Avenue property is a two-story, three-unit multi-family residential building located in Mission Terrace, constructed in 1900 and currently owned by Tong Wai Jer. The building has a concerning history of unauthorized unit conversions, with multiple complaints and enforcement actions between 1997 and 2009 regarding an illegal ground floor unit, and more recently, an active complaint from 1997 about an illegal basement unit. The property has experienced significant habitability issues in the past, particularly in 1995, with multiple tenant complaints about inadequate ventilation, water leaks, electrical issues, and safety concerns including lack of proper egress in bedrooms.

While some of these historical issues were addressed, as evidenced by the removal of the illegal ground floor unit in 2000, the building's maintenance history shows recurring infrastructure concerns. Most recent concerns center around external maintenance issues, particularly with the sidewalk, as evidenced by multiple 311 calls in 2024 regarding tree root damage to the sidewalk. There have also been recent incidents involving blocked driveways and street cleaning matters, though these are more related to external property management than building conditions.

The most pressing current issue appears to be the ongoing tree root damage affecting the sidewalk, which remains an open concern as of late 2024. The building's permit history shows some maintenance and improvement work, including kitchen and bathroom remodeling in 1985, installation of a garage driveway in 2006, and efforts to address illegal units, though many of these permits are now expired. The property's records reveal a pattern of historical maintenance challenges and unauthorized modifications, with the most recent issues primarily relating to exterior conditions rather than internal unit habitability.