Recent research from Johns Hopkins University has found that affordable housing, which by rule of thumb is about 30 percent of a family’s income devoted to housing costs, has a positive connection with low-income children’s cognitive development.

But when low-income families spend more or less than 30 percent of their income for housing costs, the children’s cognitive development suffers.

Sandra J. Newman, professor of policy studies and director of the university’s Center on Housing, Neighborhoods and Communities, and senior research associate C. Scott Holupka focused on families with children younger than 12 and with incomes at 200 percent or less of the poverty level. They also relied on data from the Panel Study of Income Dynamics and its Child Development Supplements as well as the 2004-2009 Consumer Expenditure Surveys.

“Families who are spending around 30 percent of income on housing have children who are performing better on cognitive tests,” says Newman.

The researchers also found that families paying 30 percent of their income on housing are devoting more money to enrichment for their children, such as books, computers, and educational outings. In fact, those families spend $125 more per year on child enrichment than those who are paying only 10 percent of their income on housing and $75 more per year than those who are paying 50 percent of their income on housing.

“We do corroborate conventional wisdom that if you’re spending too much of your income on housing, your children are going to suffer,” Newman says, adding that housing cost burdens can put tremendous stress on where a household’s remaining money is spent.

What the researchers didn’t expect was how spending less on housing would impact children’s cognitive skills. Newman says some poor families who are spending 10 percent or 15 percent of their income on housing costs are not getting good housing in return. “It’s the worst housing in distressed neighborhoods,” she says.

The research was funded by the MacArthur Foundation as part of its How Housing Matters initiative.