Who doesn't want a treehouse for their kids, or even for themselves? But if you can DIY this project, you can save a lot of money without sacrificing safety.

To be fair, the Innis tree house isn’t really a tree house. “It’s a tree house without a tree,” said Matt Innis, builder and owner. It’s an 8-by-8-foot house elevated 6 feet up on stilts. And it’s ...