The Free Spirit Sphere - inspiration for the relocatable home of the future

One of the major advantages of the design is that the 500 lb wooden sphere can be easily moved from one location to another within the forest by ropes and tackles. "I have slung them from tree to tree during placement or removal," says Tom. "They can also be helicoptered in to remote sites."

"Climbing the trees is the most difficult yet exhilarating work. Typically it takes a crew of three men a day to get a sphere rigged in the trees. Then it takes several more days to set up the stairway and suspension bridges. The whole set-up comes down in a day and vanishes without a trace.

Safety from falling trees

One of the issues of living in any forest is that of falling trees, a problem the unique suspension concept of the Free Spoirit Sphere overcomes elegantly. There are four attachment points on the top of each sphere and another four anchor points on the bottom. Each of the attachment points is strong enough to carry the weight of the entire sphere and contents.

"The suspension concept is to have the sphere and web function naturally in its environment. If something really big, like a tree, falls through the web then some strands break and let it pass through. The sphere remains suspended by the remaining strands. A major disaster like that is possible but not likely. The spheres are well adapted to life in a large mature forest," says Tom.

Swaying in the breeze

A suspended sphere is tethered by three nearly vertical ropes, to each of three separate trees. This distributes the load over the three trees and results in a stable hang. The sphere resides in the centre of the triangle formed by thetrees, and can be any height from two metres to thirty metres off the ground. As the spheres are light (250 kg) in comparison to the weight of a human, when somebody inside moves, so does the sphere. "As the rope tethers are almost vertical, the treetops can move considerably while hardly moving the sphere at all," explains Tom.

"A sphere can be as high as the trees will permit. The limiting factors are the size and spacing of the trees. Among the big old growth forests on the west coast of Canada with the giant Douglas Firs, a sphere could be as high as 35 meters (120') or more."

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