More on “Empty Houses”

I recently saw a Facebook post asserting that San Francisco has 30,000 vacant units, so therefore no market-rate housing should be built.   So I looked up Census data on these allegedly empty units. It is true, according to the Census Factfinder website, that there are 30,000 or so unoccupied housing units in San Francisco. Does this mean that they are completely idle?  In fact, no.  More than half of these units were (as of the 2010 Census) currently for sale or for rent. 18 percent for for seasonal use (presumably, second homes).  Only 5 percent are rented or sold but unoccupied.  The rest are “other vacant”. whatever that means. Bottom line: half the vacancies were in the process of being sold or rented.  A little under a fifth were second homes.  About a third we don’t know much about.