1320 21st Ave, San Francisco, CA 94122

The property at 1320 21st Avenue in the Central Sunset neighborhood is a two-story multi-family residential building built in 1910, currently owned by the Annie Y M Chu Trust. The building underwent significant modifications between 2012 and 2014, when a rear horizontal addition was completed to convert the single-family structure into a two-unit apartment building.

This substantial renovation, valued at $280,000, included the addition of two kitchens, five full bathrooms, new water heaters, electrical rewiring with three new meters, and the installation of new furnaces and bathroom exhaust fans - with all related permits showing successful completion. Despite these improvements, there have been recent concerns regarding the property, with multiple reports of garbage and debris (nine instances between October 2024 and January 2025) near the property, though most of these cases were promptly resolved and required no further action by city services.

A proposed additional unit conversion in 2016 was officially cancelled, and while there were associated permits and planning records for this work, it shows the owner's decision not to pursue further modifications at that time. The building's infrastructure appears to have received several upgrades during the 2012-2014 renovation period, including comprehensive electrical, plumbing, and heating system improvements, suggesting a more modern and reliable living environment compared to its original 1910 state.