Mapping the Differences Between Multi-Family and Single-Family Housing Costs

The city of Seattle provides the geography and market for a housing map that illustrates the differences between single-family and multi-family housing in terms of affordability.

2 minute read

August 31, 2017, 8:00 AM PDT

By James Brasuell @CasualBrasuell


Puget Sound

SEASTOCK / Shutterstock

Margaret Morales writes the text to accompany an ambitious new mapping project by the Sightline Institute. In the article, Morales introduces the story of a rental home comprising two units in Ballard, a neighborhood in Seattle, which was recently redeveloped into four rowhouses.

Where one home once stood, now there are 4. The homes in the new rowhouses are each, at 1,160 square feet, almost as big as the old house’s two units combined, which totaled 1,360 square feet. The rowhouses have two bedrooms and 1.5 bathrooms each. And, of course, they’re new, not a century old. They have dramatically improved insulation, wiring, plumbing, and safety features. They each sold in 2016 for more than $530,000, for a total of $2.3 million. That’s more than four and a half times the 2014 sale price of the old house, but of course, building them cost a lot, too.

Morales acknowledges that the story sounds like one of loss, and a developer getting rich while moving the city's housing stock further out of reach for most of the city's residents. But, Sightline also sees another side to the story—if the lot had been zoned for single-family zoning the blow to the city's affordability might have been worse.

To scale-up the implications of this story from Ballard, the Sightline team created a map in answer to the question: "Do multi-family homes, like the rowhouses in Devin’s story, or things like condominiums, townhomes, and the four-packs popping up across the city, offer Seattleites cheaper or more expensive housing options than single-family homes?"

The conclusion Morales gleans from the map: "Multi-family homes are offering Seattleites cheaper homeownership alternatives to single-family homes." 

Wednesday, August 30, 2017 in Sightline Institute

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