1247 41st Ave, San Francisco, CA 94122

The two-unit residential building at 1247 41st Avenue in San Francisco's Outer Sunset neighborhood is a 2-story flats & duplex structure built in 1947, currently owned by Christopher Chase Mangone. The building has undergone several significant improvements over the past decade, with the most recent major renovation occurring in 2022 when the property received window upgrades, including the replacement of four street-facing windows with aluminum-clad wood frames and twelve non-street-facing windows with vinyl frames, achieving U-factor ratings of 0.30 or better.

This work had an initial permit cost of $35,248, with a subsequent revision adding $2,898 to the project total. Between 2011-2012, the building underwent substantial retrofitting including the replacement of two furnaces, installation of gas piping for a dryer, and electrical upgrades to kitchen and bathroom plugs, along with work on two electrical panels, all of which were successfully completed.

The property has maintained regular residential function with few reported issues, though there was one infrastructure concern reported in December 2019 regarding pavement defects on the street outside the building, which was addressed by the Department of Public Works. More recently, in October 2024, there was a double parking complaint logged with the MTA and subsequently closed, though this incident was more related to street enforcement than building conditions or maintenance. The building's record shows consistent maintenance and upgrading of essential systems, particularly focusing on energy efficiency improvements and modernization of basic utilities during the 2011-2012 renovation period, with the most recent improvements focusing on window replacement and energy efficiency in 2022.