FRIDAY HARBOR, Wash. — Here in the San Juan Islands of northwest Washington State, where a severe shortage of affordable housing threatens the economy and the community, a small nonprofit group has found an unlikely way to help anchor families that are struggling to stay — by lifting up unloved houses in Canada, hoisting them onto barges and hauling them to where they are needed.

The houses are small by modern standards and old, built in the early to mid-20th century in a booming suburb of Victoria, British Columbia, where eager buyers are now clearing the land to make way for new construction. But the structures had what builders call good bones, and the group, the San Juan Community HomeTrust, discovered that the cost of transporting them across the Haro Strait from Canada and restoring them here was comparable to the cost of building from scratch.

The project met a rapidly growing need: A surge of tourism and vacation home buyers in San Juan County — an archipelago of islands about 70 miles from Seattle, reachable only by air, boat or ferry — has gone hand-in-hand in recent years with a decline in fishing, shipping and agriculture jobs that once supported a middle-class island life. The number of people living in poverty in the county has risen about 17 percent since the end of the recession in 2009, according to census figures, even as the economic recovery in Washington and around the nation gained steam.

“It’s kind life or death to keep our working families here,” said Peter Kilpatrick, the project manager in refitting the houses to be imported by the San Juan Community HomeTrust. When the rewiring, painting and structural repairs are finished in June, buyers who have already met income and residency requirements can take possession.