Some of the tips in building a good tree house include choosing the right tree, keeping stability in mind, building sections of the house on the ground before hoisting them and using the right fasteners.
Begin by choosing a healthy hardwood tree that is neither too young nor too old for maximum support. Its branches should be at least eight inches in diameter. The best trees for this project include beech, oak, maple and hemlock.
While building the house, consider its stability and weight. Build the platform close to the trunk and add diagonal bracing to enhance support for uneven loads.
Level the floor of the house by laying beams across the branch and shimming them until they level. Alternatively, cantilever the beams out from a trunk and support them from below or above. If you are building a heavy house, you may use multiple trees, and to level the floor, run the beams between the trunks of different trees. Levelling the floor makes it easier to build the rest of the structure.
Build the sections of the house on the ground and lift them one section at a go. It is safer and easier to build the main sections on the ground before hoisting them into position.
Finally, assemble the section and fasten the house to the tree using lag bolts. Lag bolts cause less damage to the tree than through bolts.