The Old New Way to Provide Cheap Housing

``Rooming houses, boardinghouses or single room occupancy (S.R.O.) hotels used to be ubiquitous. President Thomas Jefferson stayed in a boardinghouse for several months before moving into the White House. At the seedier end, S.R.O.s largely disappeared over the past half-century, partly because of zoning and economic development projects. In Houston I dropped in on a home operated by PadSplit, a company that offers furnished bedrooms for working-class Americans. PadSplit, which is something like a long-term Airbnb for rooming houses, has housed 22,000 people so far and is growing fast.''