This summer I built a tree house. For as long as I can remember I've wanted to build a tree house, but I've never been able to because I was too young and lacked the necessary skills. But this year, I was able to build it! This tree house took me about two months to build, not working full time. The size of the base of the tree house is 58 inches at its' widest and 55 inches at its' longest. The size of the bench is 14 inches deep and 43 inches long. I hope in this Instructable to explain most of how I built my tree house.
Step 1: Tools Used
The first thing to mention is all or most of the tools that I used. The tools I used were saw horses, clamps, drill bits, levels, and quick square, tape measure, pencil circular saw, corded drill, and a cordless drill. The saw horses were used to hold the lumber while I cut it to proper length with the circular saw. I used the quick square, tape measure, and pencil for marking the lumber before I cut it. I used the levels to make sure the support beams, railings, and bench were level and flat. I used the clamps to hold things together while I drilled pilot holes with the cordless drill and drove in screws with the corded drill.
Step 2: Materials Used
I will also mention the materials I used. I screws I used were 1.25inch screws, 2.5 inch screws, 3 inch screws, 3.5inch screws, and 4 inch screws. The 4 inch screws were usually used for anything that was attached directly to the tree--like the foot and hand holds. The lumber I used were 2x4s (for the floor boards, horizantel railings, and foot and hand holds), 1x3s (these were for the vertical railings), and 2x6s (used for all the support beams and supports for the bench). The Finish I used, because the lumber was not treated, is Thompsons WaterSeal which is a water proofer and stain.
Step 3: Foot and Hand Holds
In my tree house I used 18 hand and foot holds. The foot holds are made out of 6 inch 2x4s with a bevel cut off part of the top to add a better hand hold. The angle of the bevel is between 30 and 40 degrees. Then I drilled two pilots holes in each hand/foot hold and then drilled a counter sink hole in the same spots about 3/8th of the way through. This made it so that the 4 inch screws would get further into the tree and make it more secure. Screwing the hand/foot holds into the tree was a little bit tricky because if I didn't put all my weight into the drill then the screw would strip. After they were all installed, I painted some of them so that the hand/foot holds would not be extremely noticeable from the road. But after I did finally get them all installed, I found that it was not that hard to climb up at all.
Step 4: Tree House Support Beams
After the hand/foot holds were done it was time to work on the support beams. These were the hardest to install because every single board had to be level and installed parallel to each of the other boards. To get up to where the base was going to be I had to attach 3 pallets together, because I didn't have a tall enough ladder. The first support beam to be installed was the dark brown one in the picture. This board had to be level and at the right height to keep all the others boards level. getting this board right was the hardest of the 5 and I needed help from two other people. After that was installed with the assistance of others, I installed the middle beam. I used an L-shaped piece of metal to attach the one end to the tree and and couple 2x4 scraps to attach the other end to the dark brown board. The third beam to install was on the left side of the picture. This board I left a little long, attaching one end to the tree by attaching its end first to a 6 inch 2x6 and then screwing that into the tree. Then after I installed the other end of the board I left long to the brown board with 2x4 scraps, I cut it to the same length as the middle beam. Before I installed the fourth beam, I installed some floor boards to make it so that I could get to the spot of the fourth beam easier. Then I install the last beam leaving it long until I installed it and then cut it to the same length as the middle and left beams. This last beam did not have much support at all, so after installing some more floor boards, I installed the diagonal beam to hold up the fourth shortest beam. After that all the support beams were done and I could start working on the floor boards.
Step 5: Flooring
After the support beams were finished, I was able to work on all the floor boards. This was the most fun part because it was kind of like a puzzle. For the floor boards I used 2x4s. I started with the shortest boards working my way up to the longest boards. The thing I had to decide now was how wide I wanted it. To decide this, I found out first how high I wanted the railing (32-26 inches) and then I found the right width I wanted. If it was too wide the railing would have to be higher and I didn't want this because I didn't have an endless supply of lumber. I used two 3 inch screws per support beam it crossed (picture should show this). To space all the floor boards, I used my quick square. To install them I would push floor boards against the last board installed with the quick square in between and then drive in one screw. Making sure the board was still aligned properly I would screw another screw into a different beam then the first. If the floor board was still aligned I could screw in the rest of the boards without worrying about alignment. Doing this I installed all the floor boards except the last boards which I first attached small railing post to. More on this in "Installing the Railing" step.
Step 6: Railing Posts
I added three main posts 36 inches tall to the railing to add more support. I screwed each post one on each support beam with three 4 inch screws. These had to be as parallel to each other as possible.
Step 7: Installing the Main Railing
For the railing fences I used 1x3s and were 2 ft long. To install most of these, I attached the railing fences to the three last floor boards as you can see in the 2 first pictures. I attached the railing fences with 2 inch screws in the floor board and 1.25 inch screws into the lower horizontal railing. This made installing the railing fences in the tree house a lot easier, quicker, and safer. If I didn't do that I would have had to lean out over the edge and screw in each railing fence one at a time, taking forever and also more likely to possibly slip and fall. After all the railing fences were installed I then started building the horizontal railings. The first horizontal railings installed were the lower ones. When I attaching these to the 2x4 beams I used 3 inch screws and when attaching them directly to the tree, I used 3.5 or 4 inch screws. I then screwed all the vertical railing fences to the horizontal railing with 1.25 inch screws. For the upper I put the whole railing together on the the ground and then had people lift it up to me in the tree house. I used clamps to hold it in place and then screwed it into the three support beams and in both three trunks. The overhanging part is what I plan to use as a tarp canopy base extended out from the tree house to allow more room. After those railings were done I worked on the railings that went underneath the bench.
Step 8: Railing Underneath the Bench
This railing underneath the bench also is used as a ladder up to the bench. For attaching these and keeping them strong and sturdy, I cut out L-shaped pieces of 2x4s for each end of the railings. I had three railings and cut out six L-shaped pieces. I installed these first with the assistance of a sibling. This is also where I needed a level. I had my sibling hold the board where I wanted it and also leveled it. Then while he held it still, I screwed in the L-shaped pieces. Doing this I installed all three railings about 8-9 inches apart. Next it was time to install the bench.
Step 9: Installing the Bench
It was now time to install the bench. This whole bench I had built a couple years before, but was just sitting it the garage because the legs were too long and not sturdy enough. So all I had to do was unscrew the legs and attach it to the tree. To do this I first installed two 1 foot 2x6's to the tree to hold each end of the bench. Before I installed the second holder I made sure it was level by running a scrap piece of 2x4 across both holders. Then I screwed the second holder into the tree. I used six 4 inch screws in each of the holders. After that I was able to just put the bench on top of the holders and screw it in. I screwed the bench into the holders and the tree for extra strength. For the railings that went behind the bench I also used some L-shaped pieces. This was harder and more dangerous then the railings underneath the bench. With the help of a sibling to hold the railings in the right place and level, I was able to screw them into the tree with 3.5 and 4 inch screws.
Step 10: Putting on the Waterproofer
Putting on the waterproofer was the easiest. After reading and following the directions, I used a large paint brush to brush on the waterproofer on the whole tree house and then I let it sit for 2 hours to dry, like the instructions said to. After that whenever it rained instead of soaking into the wood it beaded up and dried much faster. This should also make the whole tree house last a lot longer.
Step 11: Adding a Pulley With a Bucket
The last step in building the tree house was adding a pulley system. This would allow me to bring things up to the tree house much easier. I wanted the bucket to be able to come higher than the railing so I attached the pulley to the tree higher up than my head. The hardware I used was an eye bolt, a heavy duty carabiner, rope, an old ice cream bucket, and, of course, a pulley. I drilled a pilot hole in the trunk and then hand screwed the eye bolt in. Then I attached the pulley with the carabiner. One of the the rope was tied to the railing (third picture) so that the end with the bucket would not touch the ground.