"The treehouse platform frame is a basic deck construction, but done with 2x6s to save weight — and 12” on-center to maintain strength. I framed in a trap door opening, and built using joist hangers and nails. I used a $49 cordless palm nailer, because I’m bad enough with a hammer on the ground, much less swinging it at odd angles 30 feet in the air. I’ll never go back to a hammer now if I can use the palm nailer, BTW."
You can "hang" a tree house on flexible, sturdy slings. These are more flexible in a storm and can be more easily adjusted to changes (and growth).
anyway, thanks for the explanation. what about if he tar-sealed the area where the bolts go in to prevent rot / fungus? also, i'm thinking the bolt itself would give support where the wood had been drilled out, similar to how such steel pieces are sometimes placed inside human bones to add support.