Planning for a tree house but I have some questions

[forgeblast]

I want to run past you my plan for my kiddo痴 tree house. She is four this year and wanted one last year but I just didn稚 have the cash saved up for the lumber and supplies. This year I am ready though.

Platform will be 8遅8 and built out of 6x6痴.
I plan on sinking 6x6 posts into the ground. These are 8 so I will put them in 3 giving me a platform height of 5 (just enough to make my wife nervous). I do have some 12 that I can cut in half to make a lower platform. I need to dig the holes first to see where I can place the tree house since I know the rock that is in that area.

Question 1: I plan on gravel only no cement to save the posts from rot, and to remove them if I ever want to use the area. Is this ok if I compact every 3 inches, use 2b or pea gravel? (I will have 3 in the ground, if I can get them in deeper I will but knowing the area I will hit stone.)


After the 6x6 posts are in I will frame the top platform using 2x6痴. I will bolt them through the 6x6 post. I will then put in 6 more 2x6痴 (on 16鋳 centers) using hangers.
After the platform is done I will use 2x4痴 on the sides of the posts to add stability in an x fashion.
Question 2: Will 2x4痴 provide enough stability or should I go with a 2x6?

After the sides and top are braced I will bring in some ｾ pt plywood for the floor of the house. I want the house dimensions to be 6x6 with a 2 deck area on two sides. I will use pt decking to cover the 2 area.

I then plan on making this type of house. trapping shack - Survivalist Forum




Question 3: What is the best way to attach the vertical end posts to the pressure treated plywood. I am thinking of using a 2x6 under the decking nailed into the joists and using a lag screw that passes through some plate steel that I have to keep the screw from pulling through the floor. I also plan on using timberlock screws to screw the first row of side poles into the deck. I don稚 want uplift to rip the house off the platform.

Then It will be just stacking and nailing (or screwing) in the side poles until I get to the top of the post. (I am thinking the vertical corner posts will be 6 high. (This way if I don稚 move it I can always use it as an archery stand).

Then I would need to do the roof and put tin on it.

If I did not clarify something please let me know, I have this project in my head and I am trying to work it out on paper atm.

After the roof is on, then the railing would go on, along with the stairs.

I also need to think about chinking the logs. I am thinking of taking my power planer down the top and bottom of each log to provide a flat surface to seal better.


I dont want to build it on the ground, it would become a place for more groundhogs to live.

 

[RxRatedZ71]

Is this a father- daughter project? Sounds like it can work for a "doghouse" for you too!

 

[forgeblast]

It is a father daughter project, the deal with my daughter is that everytime she learns to use a tool the right way she gets to keep it in her tool bag.
She has a pretty good collection already.
In the barn I have a whole area set aside for her, with wood, nails, glue, and paint. She gets to just build and make things with out worrying about the mess. She is a good cleaner upper, but the barn is for sloppy, (fun) projects.
If this design works, I want to make a few more for tree stands. But I am going to take it slow on the projects this year and spend more time with the girls.

 

[quicksandfarmer]

My thoughts:

The big thing to worry about is the posts moving. With 8' posts and 5' above ground and 3' under, and the posts tied together and only 8' apart, I think it's going to be pretty secure against racking. The only way those posts are going to move side to side is if the soil yields, and packing the holes with tamped gravel should prevent that. If you're at all worried a couple of pieces of cross-bracing should set your mind at ease. However, the structure looks like it's going to be quite heavy, and I would worry about the posts sinking -- and sinking unevenly, causing the structure to twist. You may need to put the posts on concrete pads to spread the load.

 

[forgeblast]

Thank you I didnt think of it sinking unevenly. I will go with the concrete pad for piece of mind.
Do you have to put anything under the pad, is it on bare dirt or on compacted gravel?

 

[Dr Dave]

Sounds like a fun project, I am building one with my grandson this summer, I like the tool reward program!

Dave

 

[jimmyj]

I want to do a very similar project down back at our place. Here is what I was thinking....
1. Bottom of each post hole packed with rocks and then 3/4" gravel, about 4 inches deep before the post goes on top. Holes to be 4 feet deep due to frost in our area. Was going to use cedar posts (actual white cedar tree logs) or PT 6x6
2. Cross brace all posts 2 ways. First, big X shaped crosses to prevent leaning. Second, a perimiter of 6x6 timbers right at ground level from post to post to post. That way it won't sink.
3. Notch each post at the top to make a saddle to put my 2x10 or 2x12 or whatever it is I use for the perimiter floor joists. Then put joists on 16" centres just like I'm making a giant suspended deck.
4. The walls would be "post and beam" with plywood on them (either with siding over top or the kind that looks like wood siding). This will further help the square rigidity of the structure.
5. Some extra bracing would be put in between floor joists etc just for extra safety. I was also thinking of putting a 5th post right in the middle to stop any chance of bounce. If I do that, I will have to cross brace it too like I do the 4 corner posts.

Like you, I want to have the option of removing the structure later or changing it if my needs change. I think it would be fun to have an elevated tree house with a wee porch on the front to watch the world from.

Anyhow, just some extra thoughts for you.

 

[forgeblast]

I like the slide attached I may have to do that!
Here are some links to elevated deer stands I have collected to help me visualize the bracing
Anyone build their own elevated box blind?
Elevated Deer Blind
Need help with an elevated hunting blind
Sample pages from bird hide plans | Treehouse Guides
(this one is a good one!)

Notch each post at the top to make a saddle to put my 2x10 or 2x12 or whatever it is I use for the perimiter floor joists. Then put joists on 16" centres just like I'm making a giant suspended deck.

Thanks I will have to do that.

I was also thinking of putting a 5th post right in the middle to stop any chance of bounce. If I do that, I will have to cross brace it too like I do the 4 corner posts.
That thought did cross my mind. But I will off set the house a bit to have some porch I guess I will have to have my buddy "Big J" jump on it a few times to see how much its moving

 

[jimmyj]

Haha. Can't have too many pals named "big J"....

 

[radioman]

Your plan sounds fine- esp. for pea gravel around posts. What I would do if sinking is an issue is put pt 2x4's along the bottom right on the ground around the perimeter. use that as a border to add sand too make a sand box for those hot days so she has shade. The 2x4's will give some resistance from sinking - I wouldn't worry about it rotting from ground contact - I have same thing on my kids slide and its still there after 12 years. I moved it once with my tractor to a better spot and its still holding strong on bottom.