New Housing/Mobility Measurement For Affordability Is 45%

The housing affordability rule of thumb is that you should not pay more that 30% of your income in rent or mortgage payment. Yet that ratio doesn't include the transportation costs that vary by community. What would it be if it was included?

1 minute read

May 12, 2010, 6:00 AM PDT

By Irvin Dawid


The current 30% yardstick fails to include transportation costs, including costs of vehicle ownership, insurance and operation. What if a new ratio was developed to include the costs of mobility that varies among communities - and went further than just measuring commuting distances?

The Center for Neighborhood Technology had done just that through research, dubbed "H+T Affordability Index"that shows that "the combined cost of housing and transportation shouldn't exceed 45 percent of your income." (Click on the map to see the H+T Index where you live).

Their "study was based on demographic, economic and transportation data from 337 U.S. metropolitan areas. The concept is helping shape new federal and state policies to encourage development of more compact communities that aren't so far-flung and promote less driving."

"Length of commutes is not the dominant factor. Each neighborhood has a unique fingerprint of such costs. It's determined by the length of commutes and trips to run errands...The more spread out a neighborhood, the more people depend on cars, often needing more than one. The availability of mass transit is large factor."

Thanks to Metropolitan Transportation Commission

Friday, May 7, 2010 in The Arizona Republic

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Cover CM Credits, Earn Certificates, Push Your Career Forward

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

June 25, 2025 - Diana Ionescu

Person wearing mask walking through temporary outdoor dining setup lined with bistro lights at dusk in New York City.

Restaurant Patios Were a Pandemic Win — Why Were They so Hard to Keep?

Social distancing requirements and changes in travel patterns prompted cities to pilot new uses for street and sidewalk space. Then it got complicated.

June 19, 2025 - Diana Ionescu

Aerial view of town of Wailuku in Maui, Hawaii with mountains in background against cloudy sunset sky.

Maui's Vacation Rental Debate Turns Ugly

Verbal attacks, misinformation campaigns and fistfights plague a high-stakes debate to convert thousands of vacation rentals into long-term housing.

July 1, 2025 - Honolulu Civil Beat

Aerial view of new neifhborhood under construction with enpty lots in foreground.

In California Battle of Housing vs. Environment, Housing Just Won

A new state law significantly limits the power of CEQA, an environmental review law that served as a powerful tool for blocking new development.

1 hour ago - CALmatters

Low-rise Pearl Sreet mall in Boulfer, Colorado.

Boulder Eliminates Parking Minimums Citywide

Officials estimate the cost of building a single underground parking space at up to $100,000.

2 hours ago - Boulder Reporting Lab

Two-story buildings with porches in walkable Florida neighborhood.

Orange County, Florida Adopts Largest US “Sprawl Repair” Code

The ‘Orange Code’ seeks to rectify decades of sprawl-inducing, car-oriented development.

3 hours ago - CNU Public Square

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.