DIY Network

How to Build a Tree Fort

Building a tree fort from a kit is much less expensive and easier than building one from scratch.

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Step 1: Unpack the Tree Fort Kit

Follow the manufacturer's step-by-step instructions to unpack the box.
A lot of the work on the tree fort has already been done at the manufacturer, such as the windows and panels.

Tip: You'll need help unloading the kit due to its size and weight.

Take measurements to figure out where you want the tree fort. When digging postholes, it's best to move about 10' away from tree. This way you are less likely to hit any of the large roots.

unpack tree fort kit

Step 2: Attach the Legs

Turn the base upside down to put on the legs. Tap 3/8" galvanized carriage bolts into the pre-drilled holes in the 4 x 4s. Start the nuts but don't tighten them down until all the posts are in place.

turn base upside down to put on legs

Step 3: Attach the Cross Braces

Attach two cross braces to each 4 x 4 (Image 1), which will give the structure added strength. Once they are all in place you can then tighten the nuts down.

Note: Be careful not to over tighten the nuts because the cedar is fairly soft.

Tip: Run a short piece of rebar through the post (Image 2) to help stabilize the footings in the cement.

Step 4: Turn the Structure Over

Turn the structure over.

Expert Tip: When deciding where to place the freestanding tree fort, bear in mind that it would be great and convenient to be able to watch your children from the deck or patio. Also, it's a good idea to blend the fort in with the surrounding branches from the tree or trees.

Step 5: Drill Holes for the Footings

Use a power auger or posthole digger to drill holes for footings. When drilling the holes with an auger, if you feel any resistance you've probably hit a root. If this happens you may want to move over a few inches.

Note: The cost to rent a power auger is approximately $150 a day -- and add a $50 delivery fee.

drill holes for footings

Step 6: Add the Gravel

Put about three scoops of gravel in each of the holes to provide a base for the post to sit on as well as providing drainage.

add gravel to provide base for post

Step 7: Add the Cement

Place the posts in the holes, and level the base using a 6' level. After assembling the structure, pour fast-drying cement into the holes and add water. Give it a good stir and the concrete will set overnight.

Step 8: Secure the First End Panel

Place the first end panel into notch. Secure it along the bottom by drilling 1-5/8" deck screws into the pre-drilled holes.

Note: Have someone hold on to the first panel while handing up the next wall panel.

secure first end panel

Step 9: Attach the Rest of the Panels

Connect the second panel to the first utilizing the pre-attached corner trim. Repeat the process with the remainder of the wall panels -- with screws along the bottom and corners.

attach rest of panels

Step 10: Assemble the Roof Panels

Slip the first roof panel onto the special notches built into the top of the end panels. Use screws through the top of the side wall into the roof fascia to hold the roof panels into place. Push the second roof panel into place.

assemble the roof panels

Step 11: Assemble the Dormer

Assemble the dormer and set it into place over the frame of the roof. Secure it from inside with screws.

assemble dormer and set it into place

Step 12: Secure the Tree Fort

Pour fast-drying concrete in the holes that support the posts. You can do this with an easy technique -- instead of using a wheel barrel simply pour the concrete mix right into the hole, add water and give the compound a good stir. Let it setup overnight and the fort will be on solid footing by morning.