Everyone loves a treehouse. But for some, venturing into the
trees can seem like an almost impossible dream. Forever Young
Treehouses is a Burlington, Vt.based nonprofit
organization that helps those dreams come true by building
handicapped-accessible treehouses for children with
It's a demanding craft. Because many of the children must use
wheelchairs to get around, access to the structures is provided
by long ramps. On one of the group's projects — an
Ashford, Conn., summer camp for children with cancer and
serious blood diseases founded by actor Paul Newman —
maintaining the slope at the required 12 to 1 ratio resulted in
a ramp 340 feet long.
This treehouse, at a southern New
Hampshire treatment center for the disabled, sits 20 feet up in
an oak grove. The rustic railing that flanks the 150-foot
access ramp has an appropriately playful look, but like the
ramp and the treehouse itself, it's fully ADA
"The kids actually like the ramp as much as the treehouse
itself," says Forever Young designer and builder James "B'fer"
Roth. "Rolling along it is like taking a walk in the woods, and
a lot of them have never had a chance to do that before."
Structural safety is another consideration. Forever Young works
closely with a number of engineers and arborists to ensure that
its treehouses can support the anticipated design loads, don't
damage the supporting trees, and allow for some necessary
movement as the trees sway in the wind. More information on
Forever Young Treehouses is available at the organization's
Diagonal braces that support the
treehouse deck are anchored to welded steel brackets bolted to
engineered treehouse fasteners known as Garnier Limbs, for a
legendary Oregon treehouse builder and organizer of the annual
World Treehouse Conference.
The 1 1/4-inch steel shaft of the Garnier
Limb is threaded into an accurately drilled and countersunk
hole; the integral steel collar acts to distribute crushing
forces over a wider area of edge grain. This sample was tested
to failure at about 7,000 pounds of load. The most recent
version of the fastener is heat treated for added strength and
has withstood test loads of as much as 11,000 pounds. (For more
information on the Garnier Limb, contact engineer and
manufacturer Charles Greenwood at 541/592-4100.)Pairs of welded steel "highway brackets"
are fastened in place with a stainless-steel rod that passes
all the way through the supporting trunk. This provides a solid
anchorage but also allows the LVL beams — which have been
covered with a peel-and-stick bituminous membrane — to
shift slightly in response to the wind.