Every project has milestones, those little moments that are naturally followed by a silent glance and broad smile as a complex system becomes a single complete unit.

Fully installed and trimmed, the rear deck of the treehouse looks ready for Adirondack chairs and iced tea.

Such is the case with the treehouse platform. While the signature of the professionally built treehouse is often the creativity and whimsy that shines from the structure, some of the most challenging and unique work occurs before house, rails and bridges are ever formed. The treehouse platform is, literally, the foundation of the entire project; and that foundation is utterly unlike anything any other builder faces. The platform must be sound, must be solid enough not to make occupants dive for something to hold on to, and must be engineered to handle all the forces that gravity and wind can deliver. More bolts and more attachments are not always an option, and everything from the first design sketch to the final saw cut must reflect that we are in a living host – one that must continue to thrive or all our dreams tumble to the ground.

The portion of the platform covered with exterior-grade plywood will be inside the future treehouse.

For a relatively modest treehouse in terms of square footage, the Ithaca treehouse platform offered some grand challenges. Twelve trunks that vary from 8 inches to 20-plus inches in diameter at platform height had to be worked with and around. Some of those trunks have considerable lean, and all black willow trunks have a natural eagerness to shed wind by bending in the breeze. We had to deliver the size and the spaces the girls who will inherit this place dreamed of, and we had to make sure everyone – girls and tree – will grow together as partners for years to come.

So Wednesday, when it was time for that silent glance and broad smile, the silence and the smile lasted a little longer than usual.

Deck boards are carefully trimmed to allow trunks and cables to pass through.

The platform, about 240 square feet including interior and outdoor deck space, was balanced, strong and beautiful. The two-tiered support system recommended by project engineer Charlie Greenwood showed all the strength and flexibility we will need, and was pretty neat to look at when you walk up to the site. Glulam girders from nearby Unalam Products and those black locust beams we got from the Locust Lumber Co. look unstrained by the deck structure above. The platform surface, particularly the Douglas fir boards that make up the exterior decking, feels strong to the feet and looks light to the eyes, a good formula for relaxation in a treehouse. All of this, of course, is riding atop a combination of industry-standard Garnier limbs purchased from the master Michael Garnier himself, and some heavy-duty GLs produced by fellow treehouse builder Dan Wright.

One fringe benefit of a well-designed treehouse platform -- they're pretty neat to look at from below.

As a designer/builder, it’s just wonderful to stand there and see it all work together so well. As a person, it’s even more wonderful to stand on the platform and think of none of it – just enjoy the breeze and the view and begin to feel the magic that only sweeps in when we come off the ground to meet it.
After a few days for office, design and purchasing work, it will be time to create the treehouse itself. Walls will be constructed on the ground and lifted into place, the latter being perhaps the most exciting day of any treehouse project.

Stay tuned.