The twin clapboard houses that contractor Norman Scotland built side-by-side on Warburton Avenue are what one might expect to find in Westchester County, N.Y. Modest in scale and colonial in flavor, you almost wouldn't know they were newly constructed just a couple of years ago. And with their enviable views of the Hudson River, you'd never guess that they are affordable for-sale duplexes set above apartment flats, with the flats designated as rental housing for low-income tenants.

When the village of Hastings-on-Hudson donated the two 1/3-acre parcels for residential development, it did so with the requirement that each of the paired homes be sold to a family making no more than 65 percent of the area median income (for a two-person household, that amounted to just under $45,000 per year). The buyers who now occupy the top half of each duplex—a single mom who works as a railroad conductor and a school custodian/volunteer firefighter/EMT whose wife is a homemaker—serve as landlords for the tenants below, using the rental income to help offset their mortgage payments.

With their local architecture, the Hastings duplexes effectively diffused NIMBY fears about streetscape eyesores and compromised property values. But getting to the closing date wasn't easy. The approval process for this small infill venture (located in a historic district) took four years, and the oddball site posed tremendous construction challenges, given its 20-foot drop in grade over a 30-foot run of the buildings. By the end of the two-year build-out, Scotland managed to eke out a tiny profit, but it wasn't much.

“I could have sold the houses as we were building them,” says the Yonkers, N.Y.–based builder. “Every day people came by and offered me all kinds of money because they overlook the river. Some were offering half a million.” Per the land deal with the local Housing Action Council, however, each home sold for about $200,000 in a market where the median home price is $500,000.

MAKING THE GRADE: The affordable duplexes on Warburton Avenue are carved into a sloping parcel  that most considered unbuildable. The units were bid and built at $117 per  square foot, with more than 150 cubic yards of concrete retaining  walls. Authentic clapboard siding was a requirement, per historic district  guidelines. Project name: Hastings Housing; Location: Hastings-on-Hudson, N.Y.; Builder: Landscot, Yonkers, N.Y.; Architect: Duo Dickinson Architect, Madison, Conn.; Project size: Two duplexes (ownership units above rental flats) on .3 and .29 acres, respectively; Price per home: $200,000; Square footage: 1,400 square feet (ownership residences); 600 square feet (rental units); Area median income: $59,200; Median home price: $500,000 courtesy duo dickinson architect
MAKING THE GRADE: The affordable duplexes on Warburton Avenue are carved into a sloping parcel that most considered unbuildable. The units were bid and built at $117 per square foot, with more than 150 cubic yards of concrete retaining walls. Authentic clapboard siding was a requirement, per historic district guidelines. Project name: Hastings Housing; Location: Hastings-on-Hudson, N.Y.; Builder: Landscot, Yonkers, N.Y.; Architect: Duo Dickinson Architect, Madison, Conn.; Project size: Two duplexes (ownership units above rental flats) on .3 and .29 acres, respectively; Price per home: $200,000; Square footage: 1,400 square feet (ownership residences); 600 square feet (rental units); Area median income: $59,200; Median home price: $500,000 courtesy duo dickinson architect

In many ways, the Hastings project exemplifies why so many builders are reluctant to venture into affordable housing (lots of headaches, little payoff). At the same time, some see it as a shining example of how the housing landscape can and should be reformulated to allow displaced essential workers such as teachers, first responders, and municipal employees to once again live in the communities they serve.

Project name: Hastings Housing; Location: Hastings-on-Hudson, N.Y.; Builder: Landscot, Yonkers, N.Y.; Architect: Duo Dickinson Architect, Madison, Conn.; Project size: Two duplexes (ownership units above rental flats) on .3 and .29 acres, respectively; Price per home: $200,000; Square footage: 1,400 square feet (ownership residences); 600 square feet (rental units); Area median income: $59,200; Median home price: $500,000 courtesy duo dickinson architect

EXILE TO THE EXURBS Proximity to employment is no small matter when it comes to making housing affordable. In recent years, droves of low-to moderate-income families have moved farther from their jobs in search of homes in their price range, only to wake up to the unsavory revelation that the amount they've saved on housing has been eclipsed by commuting expenses. A 2006 study of 28 major metro areas by the Center for Housing Policy found that the average working family (defined as one earning anywhere from minimum wage to 120 percent of the local area median income) spends 28 percent of its total income on housing and roughly 30 percent on transportation.

With hordes of would-be home buyers having no choice but to “drive to qualify”—often as far as 65 miles from work (and sometimes much farther) to find homes they can afford—it's easy to understand how transportation costs have come to gobble up such a large share of household budgets. Gas prices are at an all-time high, and in many cases public transit lines do not extend into exurban territory. The vast majority of workforce commuters (more than 85 percent), drive private vehicles to work, according to the Center for Housing Policy study.

Commuting concerns were partly what compelled the 1999 groundbreaking of Wellington, a compact neighborhood just 1.3 miles from the ski mecca of Breckenridge, Colo., offering modest workforce housing for middle-income families. With average single-family home prices topping $800,000 in Summit County, many of the workers who kept the resort town's chic boutiques and swank restaurants in business were commuting up to 45 minutes over snowy mountain passes to find mortgages or rents they could afford.

Boulder, Colo.–based developers David O'Neil, John Wolff, and Tom Lyon (working collaboratively under the name Poplar-house) saw an opportunity to counter the trend by transforming 22 acres of an adjacent brownfield site (a former mining property bought on the cheap as unincorporated land) into a picturesque village just minutes from downtown Breckenridge via circulator bus. Of the 122 homes built in phase one of Wellington, 98 were offered at below–market-rate prices ($220,000 for a two-bedroom duplex; $281,000 for a three-bedroom, single-family home) to local workers making 90 percent to 120 percent of the area median income. The remaining houses, offered at market value (around $375,000), were sold with the caveat that they could not be rented out for less than six months—the idea being to discourage seasonal occupancy. Deed restrictions on the affordable homes limit real estate appreciation to 3 percent annually or the percentage increase of the area median income (whichever is greater).

Zoning concessions allowing for greater density played a significant role in making the math work, says Dan McCrerey, president of Frisco, Colo.–based Traditional Neighborhood Builders, a construction entity formed for the creation of Wellington. In this case, the town planning agency's willingness to amend the county's standard four-units-per-acre metric allowed for more efficient land use.

Learn more about markets featured in this article: Boulder, CO.