639 16th Ave, San Francisco, CA 94118

The two-unit residential building at 639 16th Avenue in the Central Richmond neighborhood is a two-story flats and duplex structure built in 1921, currently owned by Fong Kuen O & Teresa Revoc.

The property has undergone several significant improvements over the past decades, most notably recent plumbing work in September 2023 involving a sewer and house trap replacement, which follows a concerning pattern of sewer-related issues at the property. Between 2018 and 2021, there were six documented instances of sewage backup problems, all involving 4-inch sewer vents, with the most recent occurring just before the September 2023 plumbing work.

The building has also seen various window upgrades, including a completed installation of aluminum windows in 1984, another attempt in 1994 (which expired), and more recently, vinyl siding installation on the back and right side of the house in 2011, which cost $17,500. While there have been some parking enforcement issues near the property, including vehicles blocking driveways in 2018 and 2019, these are external matters not directly related to the building's condition.