Compared to other cities—from New York to Portland to LA, from Chicago to Minneapolis to Boston— Seattle is at the bottom of the list, along with San Francisco, when it comes to the percentage of households with kids.

Nationwide, about 30 percent of households have kids. In King County outside Seattle, 34 percent of households have kids. In Seattle, that percentage drops to 19.2 percent.

In my latest "Urban Upgrade" column for the magazine, I write about a recent report from the Seattle Planning Commission (SPC) that—despite the stereotype of urban planning snobs obsessed with making the world safer for tech startups, aPodments, and dating apps—is called "Family-Sized Housing: An Essential Ingredient to Attract and Retain Families with Children in Seattle."

But grumpy single-family zoning champions who are uneasy about Seattle's apparent future as a playground for young Amazon.com employees with their bikes and Google glasses shouldn't get too excited about SPC's family-friendly report.

Connecting class politics to urbanism, the study identifies the crux of Seattle's kid-free problem as a housing affordability problem.

Connecting class politics to urbanism, the SPC study identifies the crux of Seattle's kid-free problem as a housing affordability problem. "As of 2009," the report points out, "just two percent of market-rate apartment units in Seattle have three or more bedrooms, and half of that tiny fraction are affordable to low-income families." SPC makes 11 urbanist recommendations such as increasing the flexibility of single-family zones to add non-traditional housing like tandem housing (two houses on a single lot), duplexes and triplexes, and backyard cottages.

And so, a theme emerges in all this urbanist theory. Just as I pointed out in my follow-up to a previous "Urban Upgrade" about the ped-friendly design on Bell Street where the idea was to rewind to idyllic community values, urbanism is not some Invasion of the Body Snatchers plot to fluoridate the water with communist truth serum. It's about building a good, old-fashioned, sustainable American city.

And why are kids important to cities in the first place? When you focus on kid-friendly design, SPC executive director Vanessa Murdock says, the results—safer streets, open spaces (“every backyard doesn’t need a soccer net,” she says)—end up benefiting all of us.

Speaking of which, when you make cities family-friendly, Murdock adds, you curb suburban sprawl, a major culprit in global warming. And raising kids with an urban sensibility now is a safeguard against generations of sprawl in the future.

You can read the previous installments of "Urban Upgrade" in SeattleMet here, here, and here.

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