Close your eyes for a moment and take a mental picture of your typical customer.

Do this everyday if you don't already tend to, and if you do, try it again.

Now, everyone be honest. Was the image that came to mind a married couple? (Okay, I'll admit, I led the witness with the image above. But, still.)

Now, have a look at this little piece of information that matters so much. Less than one out of every two American households is headed by a married couple.

So we have to ask the question. How well-matched are today's and tomorrow's new homes and communities to actual households?

This question will make no sense to many builders in many regions, who continue to see plenty of demand from among married-couple households, the prototypical snapshot image of the engine of the American economy.

For others in other markets and submarkets, however, the challenge is existential. If new homes--the way they're designed, the way they're marketed, the way they're planned in a neighborhood, the way they're priced, and the way they connect to work, dining, education, and healthcare--were more intentionally aligned with today's and tomorrow's households, would business be better?

Would it be more sustainable? Even ownership and financing structures may need to evolve if new home development and investment is to keep pace with America's changing demographic patterns in household composition.

At a recent meeting of the Urban Land Institute in Boston, we heard--around the ubiquitous issue of housing affordability challenges--of exploration of new mortgage financing that allows, say, two separate single-person households to buy an upstairs-downstairs combination of stacked quad units as a single transaction.

More floorplan design variety, new housing typologies, novel financing and ownership instruments, and a whole new language of marketing to less traditional households are baseline imperatives today in many of America's more urban regions, and that's spreading.

After building homes for married-couple households that--although varying widely by size and levels of specification and detail--functionally worked the same way for 10 decades or more, one might be tempted to believe, "everybody--married or not--lives in a home essentially the same way."

Is that true. Does a "solo" householder perceive volume, flow, privacy, order the same way as a married couple does. Do "co-livers" walk the same path through their homes as married-with-children people do? Does the financial means of a single-person household alter what he or she needs, and what they can easily live without?

The algorithms of live-ability, the daily routines, the way time passes, all the raw materials that make up one's answer to the question "how do you want to live in your home?" can amount to a dramatically new calculus of value, preference, need. Life's "capital stack of essentials--live, work, play, eat, sleep, love, and pray--may stack up profoundly differently than for those married-couple households architects have been designing for, builders building for, investors investing in, developers developing for, and manufacturers creating home systems to serve.

Here's why, according to New Strategist demographer and editorial director Cheryl Russell, who looks here at "Three Generations of Married-Couple Households." With a whole new generation--Gen Z--soon to start flooding the gates of young adulthood, ultimately claiming all the attention Millennials are currently getting in the housing market, it's high time builders and developers fully embrace household make-up for what it is and where it's going. Russell writes:

It is difficult to grasp just how much living arrangements have changed in the United States unless you mine the Census Bureau's archives to uncover the nitty gritty of the way we used to live. The most dramatic change over the decades is the decline in the share of households headed by married couples. In three generations, the share of all households headed by married couples fell 26 percentage points—from 74 to just 48 percent. Among the youngest adults, the drop is a stunning 68 percentage points! Here is the married-couple share of households by age of householder today (2018), one generation ago (1990), and two generations ago (1960)...

Paradigm comes from a Greek word for ""pattern, model; precedent, example." So, are we stuck in an old one in need of a new paradigm?