This is patently untrue, especially weighted by number of units. There may be a lot of small rebuilds of single family homes into duplexes, but the projects tha

This is patently untrue, especially weighted by number of units. There may be a lot of small rebuilds of single family homes into duplexes, but the projects that add the great bulk of housing units to the city are usually built on empty lots, parking, or small-scale commercial/industrial. 1515 Van Ness, 1 Oak, the 16th St. BART project, etc.