Prefab homes make inroads; promise efficiency

So much of what is in our homes these days is factory-made — toasters, furniture, toys — but not the homes themselves.

Most are still built on-site, as opposed to being prefabricated and trucked in. That doesn't make sense, says Sheri Koones, author of four books on prefab housing, including the new "Prefabulous and Almost Off the Grid: Your Path to Building an Energy-Efficient Home" (Abrams).