Building tiny houses, giving away tents and converting freight containers into housing all have been tried over the years to provide shelter for those who can't afford it.

But a cruise ship?

A Portland, Maine, man said he's applying for a $250,000 grant this week to study the feasibility of turning a used cruise ship into housing for those in need.

Kenneth A. Capron, who runs a Portland nonprofit that provides support to older people with dementia, said he wants to take a decommissioned cruise ship that can hold as many as 1,200 people and turn it into an economical weapon against a housing crisis that's being felt locally and across the nation.

Capron said he plans to submit an application Wednesday to the Robert Wood Johnson Foundation for the grant. If successful, he would use the money to study the feasibility of docking a cruse ship along the shore of the New England port city to serve as housing.

The analysis would look at purchase price, how much it would cost to refurbish or ready the ship and whether it should be home to mixed-income residents, homeless people or low-income workers.

Capron said he wants the vessel to offer transitional services on board, such medical staff, job training and drug counseling. He said the housing probably should not be permanent, at least not for the homeless, because he would prefer they transition to more stable, long-term shelter onshore.

He also wants to study the viability of for-profit lodging on the ship to subsidize the homeless and low-income residents on board.

"Pretty sure if we were to take any ship and use it for affordable housing we could fill it up in two days and be making money on the weekends," Capron says.

Portland has a waiting list of 1,123 families that need low-income housing, Mayor Ethan K. Strimling said.

The dire homeless and housing crisis in many American cities has inspired such outside-the-box thinking on shelter. The U.S. Department of Housing and Urban Development stated in its most recent count that the nation's homeless population "increased for the first time in seven years."

Other "solutions" to homelessness, such as the houses and tent giveaways, have achieved limited success. Community resistance, the stigma of strange-looking structures and isolation from familiar neighborhoods are some of the drawbacks.

With used cruise ships available for a few million dollars and with plenty of low-cost room to dock or drop anchor, Capron thinks the idea could be watertight.

Former San Francisco Mayor Art Agnos endorses the concept.

Following the 6.9 Loma Prieta earthquake in the San Francisco Bay Area on Oct. 17, 1989, that killed 63, injured thousands and caused the collapse of more than 100 structures, Agnos had to figure out what to do with the 300 or so erstwhile homeless who lived in single-room occupancy hotels deemed uninhabitable.

U.S. Navy Admiral John Bitoff offered the USS Peleliu, which could house more than 2,000, for a few weeks.

"I said I'll take it," the former mayor recalled, adding that the onboard sleepover was a success.

Now Agnos takes credit when there's talk of using a ship to shelter homeless and low-income people.

"I had the first idea," he said.

Capron gives Agnos credit and says the concept has also been floated in Seattle and Auckland, New Zealand.

But resistance, stigma and isolation remain concerns.

"It would be hard to get homeless people to do that," said University of Southern California architecture professor R. Scott Mitchell. "People generally want normal."

It's crucial that solutions to homelessness "are still knit into the social fabric of the local community," said Sofia Borges, director of the the Martin Architecture and Design Workshop in Santa Monica, California.

In making the transition from the street to a home, it's important "you’re not on a boat or in the desert," she said.

The confinement of a vessel could also exacerbate viruses, bacterial infections and communicable diseases already festering on America's streets. Los Angeles, which has tens of thousands of homeless living in squalid conditions in tent cities and street encampments, is battling a typhus outbreak in its skid row neighborhood.

"People could languish there," Borges said, adding it could be "a recipe for failure."

Living apart, afloat and in potential squalor would really only solve the homeless problem for people who have to look at it, some critics say. And casting undesirables off to sea has an ugly past.

"Ships have a dark and somewhat frightening history of being used to sequester and house people, including inmates and prisoners of war," Florida State University interior design professor Jill Pable said by email.

Some of Charles Dickens' "Great Expectations" takes place aboard a prison hulk, used in Victorian England to alleviate overcrowding among jails ashore. While Portland's idea isn't Dickensian, there is fear that life on a cruise ship for poor people could easily deteriorate.

"I think it’s strange to say, 'We have no more land for you, so we’re going to put you on this boat," said USC's Mitchell. "For the longer term, it is almost like a prison."

Capron, Agnos and Strimling say a skid row on the seas is not what they have in mind.

"We have a housing crisis in this town, so I’m willing to hear anybody out," Strimling said. "But I'm not interested in having a ghetto on a boat."