It happens very rarely, and when it does, it's a scandal and a total "man bites dog" story: http://48hills.org/2014/09/08/sf-planners-decide-just-fine-demolish-

It happens very rarely, and when it does, it's a scandal and a total "man bites dog" story: http://48hills.org/2014/09/08/sf-planners-decide-just-fine-demolish-rent-controlled-housing/ http://48hills.org/2014/09/08/sf-planners-decide-just-fine-d... Gabriel Ng & Architechs Inc. wants to build two new structures on the large corner lot at 26th and Clement. Each building would have three units, with three-bedrooms each. The project sponsor argued that there’s a need for family housing in the city, and that six new units, which most likely would be sold as condos, would help the crisis. But to make room for one of the buildings, the project calls for the demolition of an existing apartment building with two smaller rent-controlled units. And that’s something the city isn’t supposed to allow. In fact, when the mayor with great fanfare issued his housing directive in 2013, he made it clear that demolishing existing rental housing should only be allowed in unusual circumstances. [T]he 4-3 vote in favor was directly in defiance of city policy and the mayor’s directive regarding the preservation of existing rent-controlled housing. In the past year, the Planning Department has repeatedly refused to approve projects that involve a loss of rental units [...] The mayor has directed the Department to adopt policies which encourage the preservation of existing housing stock [as] the city’s highest priority.