Treehouse construction starts with a platform—the flat ground floor. The rest of the house is built on top.
The downward force of gravity pulls down on the treehouse. Solid steel bolts, called treehouse attachment bolts (TABs), help to secure it to the trees and support its weight. Each TAB can hold up to 10,000 pounds.
Once the Gardners’ treehouse platform was complete, the Nelson crew trucked in walls and other parts they had built off-site. Then they installed the walls and roof, and finished the details of the interior.
Construction took three weeks—then the real fun began. “My favorite thing to do is to have my friends over to the treehouse,” says Anna, now 14. “We have a great time spending the night and having a sleepover.”