The City: Dropping In, Speeding Up

The row on row of depressing brick tenements that make up the big city's slums are a familiar symbol of metropolitan blight. But when they were new in the Nineties, they were hailed as modern. They were well built, incorporated such advancements as light wells, and boasted at least one lavatory on every floor. Faced today with the staggering price of replacing them, many city planners have taken a second look, realized that renovation would be millions of dollars cheaper than tearing them down and starting afresh.

The main problem to date has been that rehabilitation is costly, time-consuming and inconvenient....