While tiny houses have been attractive for those wanting to downsize for financial or environmental reasons, there's another population benefiting from the small-dwelling movement: the homeless.

There's a growing effort from advocates and religious groups to build these compact buildings because they are cheaper than a traditional large-scale shelter, help recipients socially because they are built in communal settings and are environmentally friendly.

Many have been built with donated materials and volunteer labor, sometimes from the people who will live in them. Most require residents to behave appropriately, avoid drugs and alcohol and help maintain the properties.

There are already established villages in Olympia, Wash., and Eugene and Portland, Ore., and efforts are underway to make similar communities in Madison, Wis., and near Austin, Texas, and Ithaca, N.Y.