The average family in America today spends 52 percent of its income on housing and transportation costs, according to Secretary of Housing and Urban Development Shaun Donovan. Together, they make up the greatest portion of the average American family’s budget.

Now, those spiraling costs have set off a sea change in Washington. After years of working independently from each other, the federal housing and transportation departments — along with the Environmental Protection Agency and others — are working together in an effort to better address the cost of getting to, and from, our homes. In this exclusive interview, Donovan discusses how the federal government is reshaping policy to link housing and transportation together.

To more accurately measure those costs, the Center for Neighborhood Technology group recently released the Housing + Transportation Affordability Index, which appraises the true cost of housing based on its location, by examining the transportation costs associated with place.