Demand for the product is growing, but developers are struggling to make the numbers pencil out.
A shortage of more than 7.2 million affordable housing units exists nationwide for households with incomes at or below the poverty level, defined as 30 percent of area median income, according to the National Low Income Housing Coalition. But finding affordable housing is not just an issue for impoverished people. Typically, renters who earn up to 60 percent of area median income are also eligible to live in affordable housing properties.