SAN FRANCISCO—When buying a new home, imagine if you could look at a sticker and see how much it would cost to commute from that house to your job.

“Affordability is more than just the cost of a house,” said Shelley Poticha, senior adviser for sustainable housing and communities at the Department of Housing and Urban Development (HUD).

HUD leaders have been dreaming about the possibility of creating a sticker for a house much like the ones that are found on many appliances to inform consumers about their energy usage.

It’s part of the new thinking that’s coming out of the federal agency as officials work to connect the dots between housing and transportation.

She added that HUD officials have also seen a link between concentrations of foreclosures and regions where families have few transportation options other than driving.

Housing that appears to be affordable based solely on housing costs may not be affordable when it is located far from transit and jobs, said housing experts Wednesday in San Francisco, where the Urban Land Institute (ULI) is holding its fall meeting.

A quarter of all households in the San Francisco Bay Area live in neighborhoods where housing and transportation costs account for 65 percent or more of income.

That’s defined as an “extreme housing and transportation cost burden” by Bay Area Burden, a new report released by the ULI Terwilliger Center for Workforce Housing.

Families seeking more affordable housing in the outlying parts of Sonoma, Solano, and Napa counties are burdened with higher transportation costs, and these neighborhoods appear less affordable when both housing and transportation costs are considered.

Although housing costs have come down recently, so have income and employment levels, said former HUD Secretary Henry Cisneros at a press conference unveiling the study. “It’s just as pressing a time for families.”

Bay Area Burden, produced in partnership with the Center for Housing Policy and the Center for Neighborhood Technology, provides an analysis of the “cost of place” in Bay Area counties by examining the costs and impacts of housing and transportation.

Officials also presented a new Web site, that features the Terwilliger Cost Calculator to aid individuals and planners in understanding the true costs of housing and transportation. Users can calculate the combined housing and transportation costs using household characteristics and location.