- 1). Select a large and sturdy tree to construct the tree house around. Clip off all small branches on the tree that will be in the way of building. Try to avoid cutting off any large branches.
- 2). Measure out an 87-inch square, with the tree in the center. Dig a hole about 3 feet deep at each corner. Place a post in each hole and pour quick-drying concrete around it. Keep all the posts straight as they set.
- 3). After the concrete has dried thoroughly, begin to install the side posts. Install a post horizontally over two of the vertical posts, 5 feet from the bottom. Use hexagonal bolts with matching nuts and washers to screw the post on. Repeat this process with the remaining three sides.
- 4). Repeat Step 2, installing posts 3 feet above the previous posts. These posts are the frame for installing the sides of the tree house.
- 5). Using the remaining two posts, establish a base for the floor. Bolt the posts across two of the bottom posts on either side of the tree. These posts should be an equal distance apart.
- 6). Cut a sheet of plywood to fit around the tree. Using wood screws, attach the plywood to the support posts and the outside posts. This is the floor of the tree house.
- 7). Cut sheets of plywood to fit the sides of the tree house. Use wood screws to attach the sides to the posts. Leave a hole for the entry way. Cut out windows or fun shapes.
- 8). Bolt a wooden ladder to the tree house in the entry way. The ladder needs to be sturdy enough to hold the users' weight.
- 9). Sand the entire tree house. Pay particular attention to areas such as windows, doorways, and ladder steps.
- 10
Finish the tree house with an outdoor paint or stain. Paint and stain should dry thoroughly before using the tree house.
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