(You can read part one, part two, and part three in this series here.)

In the previous blog post in this series, I posited that (generally speaking) able-bodied individuals should be expected to pay for their housing, and that for housing to be "affordable" to an individual, it should take up no more than about 30% of their salary, both as a rule of thumb and by the federal government's own definition. But that's not the end of the story when it comes to establishing what affordable housing is.

Another major question is this: How far away from one's employment can housing be to still be functionally affordable for that worker? If I work a minimum wage job on the moon, renting a house on Earth and paying to commute daily to outer space won't cut it.

For a more grounded example, if a worker's job is in Overland Park, Kansas, but their housing is 25 minutes away east of downtown Kansas City, would that housing—meeting all criteria before considering location—qualify as "affordable housing", given the added cost of transportation? If the same job were in Independence—nearly 40 minutes away from Overland Park—would we expect that worker to change jobs to something closer to home, or move to housing closer to their job? How do our expectations change if instead of gas being $2 per gallon, it jumps to $5 per gallon?

This question of affordable housing in the context of geography is a nuanced question that doesn't necessarily have an intuitive or universal answer. But that doesn't mean answers aren't being proposed.

For example, the Housing and Transportation Affordability Index, or H+T Index, attempts to simulate what residents of a given census tract might expect to pay in housing and transportation combined as a percentage of their income. Keep in mind that "transportation" here includes all transportation, including trips to the grocery store, for entertainment, etc., so the H+T Index isn't an apples-to-apples comparison to the HUD definition or other housing-only definitions of affordability. But the H+T index is helpful for understanding that affordable housing that isn't close to gainful employment is, for all intents and purposes, not affordable.

Other factors can also play into the definition of affordable housing, including whether affordable housing includes homes for purchase as well as homes for rent; whether affordability considers the mitigating costs of roommates where appropriate; and the extent to which affordable housing could still be inadequate housing in some other qualitative way.

That said, a reasonable baseline definition of affordable housing includes the following: it should generally be paid for by the individual, should not exceed 30% of their salary, and should be available in rough proximity to their place of employment. Now, we can turn to the question we're exploring in this series: Does Kansas City have an affordable housing problem? Stay tuned.