The decision to build a treehouse has been made, now its time to consider the most important element of the treehouse, the tree. The health, size and future growth potential of the tree need to be taken into account. To be sure that the tree chosen fits the bill an arborist should be consulted. A consultation should be scheduled with a certified professional arborist (not your gardener or the local tree removal guy). A good arborist can usually be found in the yellow pages, or by referencing www.isa-arbor.com. The research the arborist does will determine what the health of the tree is and if the tree you’ve chosen will support your treehouse vision.
Certain types of trees are better suited for treehouses than others. A lot may depend on what type of tree is available to the builder on his property. Once the tree type has been identified then evaluation as to how the treehouse envisioned fits or not can be done. Deciduous trees lose their foliage, while evergreens keep it. Deciduous trees are preferred because identifying if a branch is living or dead is easier. However, particularly if the view is a concern, choosing a deciduous tree means limiting the construction period to certain times of the year – something to consider if the work is being done in colder climates where snow and rain is a major concern.
When building on a single tree, the most important factor is the diameter of the tree. Ten to twelve inches should be the minimum. A mature tree with large, well established limbs to provide a cradle for the floor system is preferable. Larger, lower branches are best suited for safe construction. Building too high in the tree is probably not a good idea as limbs tend to get weaker the higher up you go and tree movement from the wind is greater. When you’re building a treehouse for younger children or seniors keep the height low to avoid any dangerous falls. When using multiple trees for the structure, it’s wisest to choose trees that are all around the same size. If you use a bridge to move from one tree to another make sure the level of the bridge is similar on both ends.
Once the tree is chosen and the health and future of the tree or trees is determined you can start adapting your design to the tree and the support it will bear.