If you’re someone who builds things (and as a PW reader, it’s a safe bet that you are), chances are at some point you’ve daydreamed about building a treehouse. But in order to make the dream a reality there’s a lot more to it than just nailing some boards into a tree. That’s why Django Kroner, owner of professional treehouse building company and tree service The Canopy Crew decided to write “The Perfect Treehouse” – to help anyone looking to build a treehouse do it the right way. Here is a list of common treehouse mistakes excerpted from the book:
1. Building a rigid structure. Trees are going to move, period. The wind blows and nails pull. Everything comes apart and out of the tree.
2. Setting boards in crotches of trees. This weakens the crotch. This can also cut off nutrient flow and harm the tree. Plus, water can collect in the crotch and that will speed up decay of the lumber.
3. Bolting a large beam directly to the trunk. This can choke a tree to death because as the tree grows wider the cambium is pinched as it grows around the board. This can also happen over time if your treehouse frame is too close to the trunk.
4. Overly ambitious designs. Weaving branches through the room of the treehouse looks awesome and can be done successfully. But a lot of thought has to be put into where the framing is and how the tree will move. More often than not, the tree beats the treehouse from the inside out. Capturing this aesthetic is most easily done with just a few bigger branches low to their previous scaffold (remember, a twig comes from a branch, which comes from a bough, which comes from a trunk).
5. Poking too many holes into a tree. It may be comforting to see the additional bolt or series of screws, but placing too many holes in a tree can disrupt nutrient flow and kill it. You have to be especially thoughtful when the holes are close together on a tree. I like to try to spread out the impact and let each wound compartmentalize. If you have to have multiple points of contact with the cambium that need to be close together, do not stack them vertically. This can cause the wood between the holes to lose all circulation and die.
6. Building your treehouse to be too dangerous for use. This may sound obvious, but I have surprisingly seen this so often. Rickety old lumber nailed way up in a tree with a 2×4 ladder leading a slanted way to the top is an accident waiting to happen. I am all for hanging out in the very tops of trees, but if you put yourself or your friends in that kind of position, make sure you have total confidence in your design!
7. Building a treehouse that is too big for its host. This can lead to having to install ground posts or even to tree failure. If you are unsure and want to do the math to find out what your trees can hold, calculate the weight of your structure, and look up a wood load calculator online. You can type in your tree species and dimensions of the trunk and get a rough idea of what kind of stresses that wood type can withstand. Always err on the side of caution. You never want to push a tree to its limits.
For more ideas and instruction for building treehouses from site selection to design and construction, check out “The Perfect Treehouse” by Django Kroner, available now at shopwoodworking.com.