172-174 21st Ave, San Francisco, CA 94121

This two-unit, two-story multi-family residential building located at 172-174 21st Avenue in the Lake-Presidio neighborhood was built in 1921 and is currently owned by Ralph O. and Myra B. Chapin. The property has a significant history of building permit activity, with the most pressing issue being an active building violation from December 2006 regarding an unauthorized rear deck construction that prompted numerous compliance efforts.

This violation, filed under complaint number 200684924, remains active despite attempts to address it through permits and a subsequent variance request. The deck issue was eventually partially resolved with a completed permit in May 2018 that documented a $15,000 deck removal and replacement project. The building has undergone several significant improvements over the years, including a kitchen remodel in 2007 valued at $15,000 which included electrical updates, cabinet replacements, and gas line installations, along with plumbing modifications for a laundry area. The property experienced recurring sewer issues between 2011 and 2015, with multiple sewage backup incidents requiring attention from PUC Sewer Operations, suggesting potential ongoing infrastructure challenges.

More recently, there have been three garbage and debris-related 311 calls between October 2024 and January 2025, though these were street cleaning matters rather than building-specific issues. Two sidewalk defect complaints were filed in 2011 and October 2024, with the latter currently showing as an open case. The building's maintenance history includes various permits for repairs and upgrades, such as reroofing work completed in 1997 and subsequent updates to address code violations. While most historical issues have been resolved through proper permits and inspections, the outstanding 2006 deck violation and its related enforcement actions represent the most significant unresolved matter on the building's record.