This fall, workers are finishing construction on the world's largest tree house, set among 16 lime trees in the Alnwick Garden, a 40-acre public space 30 miles north of Newcastle, England. Hardly a glorified kiddie clubhouse, the three-story, 10,000-square-foot turreted spread will contain a 120-seat restaurant, private dining rooms, a bar, and a retail store. In recent years, smaller but equally opulent arboreal palaces have become increasingly popular as innovations have allowed for safer, more tree-friendly construction. "They require special engineering, because trees keep growing, and they move in the wind," says Anna Daeuble, of Seattle-based TreeHouse Workshop. "These aren't $300 backyard structures."
Examples range from lofty hunting lodges in the Poconos to 1,000-square-foot weekend homes in California to a new retreat on Woody Harrelson's Maui estate. For $15,000 to upwards of $200,000, TreeHouse Workshop will evaluate clients' trees and construct houses with plumbing, electricity, bay windows, balconies, and spiral staircases.
Still, purists warn against making your new hideaway a permanent residence. "You'd encounter all the problems of living anywhere else," says John Harris, lead architect of the Alnwick project. "It'd spoil the magic."