3147-3149 20th St, San Francisco, CA 94110

The property at 3147-3149 20th Street is a two-story multi-family residential building with retail space, located in San Francisco's Inner Mission neighborhood. Built in 1900 and containing 4 units, the building underwent extensive renovations and construction work from 2008 to 2010, including the addition of a studio and residential parking garage, relocated bathrooms, new windows, and comprehensive electrical, plumbing, and fire safety systems upgrades.

These improvements included the installation of new furnaces, electrical systems for multiple residential units, and substantial plumbing infrastructure upgrades. The property experienced several significant issues during and after the renovation period, including complaints about construction noise in 2009, foundation work without proper permits in 2007, and multiple building code violations such as rainwater drainage onto the sidewalk in 2010. More recent history shows concerns about unauthorized use of residential space, with complaints in 2013 and 2019 regarding potential illegal office/restaurant conversions of residential units.

The building has maintained active compliance with most regulatory requirements, though there have been periodic issues with garbage and debris on nearby public sidewalks, as evidenced by multiple 311 calls in late 2024. Fire safety systems have been monitored, with a 2020 sprinkler complaint found to have "no merit." Planning records indicate previous proposals for larger redevelopment projects at the property address (2401-2403 Harrison Street), including plans for a 4-story mixed-use building, though these were cancelled. The property has also experienced periodic maintenance issues requiring attention, including a current open case regarding a damaged tree as of December 2024.