LA Times has an article on Ray Cirino, an inventor who builds permaculture related objects, and who has recently finished a treehouse project in Hollywood Hills.
Cirino was commissioned to build a fun, and environmentally sustainable, place for children to play. The property is on a steeply terraced hillside so he opted to create a platform 12 feet high in a sturdy ash tree. Recycled materials were used throughout including Douglas fir for the treehouse’s floating deck.
“A stainless-steel turn buckle in the middle of the tree supports the structure. A rubber gasket underneath the steel — Cirino guesses it was a former food conveyor belt of some sort — protects the tree from ‘choking.’ As it grows, the buckle and gasket can be adjusted.”
Other features include a dumbwaiter, firepole, and a leaf-shaped shade made of recycled canvas to shield the kids from rain.