klowner.com

Foundation

Tuesday, October 11, 2022

So I told my dad about my completely half-formed idea to build a treehouse down near the river. We did a bit more scouting around and finally decided on a nice cluster of 4 silver maples. Silver maple apparently isn’t the best tree for treehouses since they have poor damage compartmentalization, but we figured if we do manage to kill a tree, we can swap out a weather treated post to carry the load.

I ended up doing a bit of research on modern treehouse building methods. It seemed like the most popular and long-term mounting solutions to trees are things called TABs (treehouse attachment brackets). They’re essentially heavy duty threaded rods with a knuckle that provides a little additional support. As it turns out, these attachment brackets are quite expensive, and since we like to re-use stuff we have laying around, we looked around the farm for some discarded material that might be sufficient.

Cutting the spirals off the old StirAtor auger

Dad found an old StirAtor auger which is a thing that goes inside a grain bin and agitates the grain to help it dry more evenly. We hope this will be strong enough for us to attempt what is (supposedly?) called a “hyperbolt”. This involves drilling a hole through the tree trunk and running the steel rod all the way through. With this plan the entire weight of the tree house (and anyone inside) will be distributed across these four bars.

StirAtor auger with the threaded auger part removed

Once we get a drill bit large enough (our largest tree is something like 16-inches thick) we’ll try running these through our support trees.

We also found some very old beams that dad is pretty sure were milled from nearby trees by some-number-of-greats grandpa. They’re quite heavy.

Antique barn beams, these things are massive