What type of screw and timber to start a tree house project?

Hello @Jerry1

There is nothing like seeing the joy of your children when they see that you've built them a tree house. Is the photo you posted the actual trees that you'll be using? If not, I suggest going with @Noyade's recommendation of putting up pictures of the trees you'll be using for the build. Once we see the layout of the trees our members will then be able to make recommendations on framing possibilities and what materials to use for the house.

We look forward to seeing the photos.

Eric

Hi Jerry,

Congrats on the first step of deciding to build a tree house ! 🙂 There's something whimsical and appealing not not only kids - adults too about a tree house - I reckon it ignites some primal satisfaction back to our origins ! 🙂

Like others have said - some pics and a sketch plan of what you're thinking is a start. That will significantly dictate how you safely go about building - both for your kids, and also the tree/s involved. Keep in mind trees grow (expand) and if using multiple trees; they also move (sway) - attaching a treehouse by bolts to multiple trees will never stay intact - the swaying generates enough force to rip bolts & screws straight out of trunks ! and will end badly...
you need to visualise a 'floating platform' mounted on attachments to each tree to allow movement.
I binged about every episode of 'treehouse masters' - Pete Nelson is based in USA and builds amazing treehouses all over the world !. he sells hardware also for DIY'ers; but was way too expensive for me to buy/get posted to australia. But from watching his shows; you get a real good idea of the concepts and engineering principles he uses to address the challenges of tree movement & growth. should be able to find eps on foxtel I think; but lots also on Youtube, facebook, and his website.
he also has an beautiful coffee table book called 'Be in a Treehouse' by Pete Nelson which has great inspiration; and also some design ideas. My Build thread on this site applies what I learnt on his shows.
happy to help with any more questions you have, and look forward to following your build - it's very rewarding !
Good Luck 🙂

Thanks guys.

This is the tree I am planning working on. It is a gumtree.

There are 4 big branches which spread from 1 meter high.

https://www.workshop.bunnings.com.au/discussion/comment/24274#Comment_24274

Hi Jerry,

Looks like an ideal & sturdy candidate ! some issues you won't have to deal with as it's a single tree; but the individual branches may still move independently, and grow over time; so attaching a solid frame between them may cause problems. I'd still look at putting individual pegs (I used high tensile M26 thread) on each branch (use a laser level or trusty length of hose with water in to get all your levels correct; and build the main platform resting on pegs like a floating platform. you could go more grandiose and have a 2nd platform where that centre trunk branches further up ! 🙂
in addition to the pegs that the platform can rest on, you can run hip braces from the outer edges back at 90o to the bottom trunk for more support on the edges. look forward to your progress 🙂

https://www.workshop.bunnings.com.au/discussion/comment/24274#Comment_24274

Hello @Jerry1

Thank you for posting the picture of your tree. Now we know what it looks like, it's time to think about the shape of the tree house and how big you want to build it. I suggest drawing out a rough design of how you want the house to look. Will you be doing a four-sided or a five-sided house? Will adults be sitting in the tree house or is it just for children? I'll be sketching up a design as well and once I've finished it, I'll post it here for you to have a look at.

If you have any other questions we can help with, please let us know.

Eric

Jewelleryrescue

https://www.workshop.bunnings.com.au/discussion/comment/74782#Comment_74782

Hi @Jerry1 @EricL

I dont want too poop the party but will screwing into the tree kill the tree. or ? As a kid my first treehouse was branches and big nails I an thinking that gum tree never died.

Or is there other ways of clamping heavy supports to the tree avaliable

Oh and there are no rules that say you cant use posts to the ground support the outer corners.

Great project have fun.

Noyade

https://www.workshop.bunnings.com.au/discussion/comment/101042#Comment_101042

G'day @Dan_M !

Wow! That is one impressive tree house you built sir!

Mine (circa 1996) was nothing compared to that. It was more of a platform for my three young sons so they could descend via a flying fox. I remember using braided steel wire (from a Hills Hoist?) for support from branches and a homemade ladder provided further support.

Looking back I could have been reported.

When my father saw it he was horrified.

But they tired of it quickly and it was dismantled around 2000. They survived into adulthood. 😁

Hi @Jewelleryrescue

"I dont want too poop the party but will screwing into the tree kill the tree. or ? "

Good question - I have seen nails, bolts, screws and wires embedded in some of my trees that have been there for over thirty years. In my case I knew once the 'thrill' of the flying fox was over, the large screws could be easily removed.

I think this is thirty years old in a Eucalyptus...

https://www.workshop.bunnings.com.au/discussion/comment/101042#Comment_101042

Hi @Jewelleryrescue

I understand your worry about the tree being damaged by the anchors applied to it. Trees are able to absorb a great amount of punishment from storms, hail and fire. The anchors being applied to it are mostly on the surface part of the tree and usually don't drive into the core. When a tree house is constructed the framing is often designed in such a way that it sits into the branches of the tree and the posts are there to provide additional support. Unless the tree is still very young putting anchors into it would damage it, but a mature tree would be able to manage.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/117427#Comment_117427

@Noyade

A great idea to fix a supporting beam.

My plan: A platform in 1M high, then another house in the upper level.

https://www.workshop.bunnings.com.au/discussion/comment/126914#Comment_126914

Hi @Jerry1

That's an excellent plan you've drawn up. I recommend putting in two supporting posts at the end so that you can turn one of them into the ladder assembly. In that manner, you'll get full support at the end of the platform. Since you're doing a second platform, the main platform has to be strong enough to hold an adult.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/133220#Comment_133220

@EricL

Thanks. What type of timber/screw shall I buy to fix the beams into tree?

https://www.workshop.bunnings.com.au/discussion/comment/137111#Comment_137111

I used treated pine self screwing M12 screws for mine

https://www.workshop.bunnings.com.au/discussion/comment/137111#Comment_137111

Hello @Jerry1

If you have a quick look at this discussion - Building a treehouse by @Dan_M, you'll see that he mentions a bolt called a TAB or a treehouse attachment bolt. The purpose of these bolts is to hold the framing assembly of the house without permanently fixing it to the tree. In that manner, the tree can keep moving and swaying without damaging the tree house. It also serves as a weight-bearing point for the assembly. Since the TAB is not available here you can use a similar bolt such as the M26 high tensile bolt that was used for Dan's assembly.

However, since you're not building very high, it might be possible to anchor the treehouse frame to the body of the tree. You'll need to do some observations and see if the tree sways very much in high wind. One other method is to build the house frame with posts so that you don't have to anchor onto the tree at all.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/139795#Comment_139795

Shall the screw go through the trunk or just nail in? WeChat Image_20221221112421.jpg

https://www.workshop.bunnings.com.au/discussion/comment/141643#Comment_141643

Hi @Jerry1

To prevent severely damaging the tree, I suggest only going halfway in with the length of the bolt you'll be using. If for example, you'll be using a 250mm bolt, you should at least have 125mm driven into the tree. The rest will be used by the timber framing of your tree house.

If you need further assistance, please let us know.

Eric

dbaarda

https://www.workshop.bunnings.com.au/discussion/comment/143032#Comment_143032

So I'm in the process of building a tree house after doing heaps of research and will eventually write my own topic covering it. But for now, the general rules of thumb about attaching things to trees are;

1. Trees don't like their bark being damaged, because it cuts their circulation above the damage, and creates an ingress point for moisture/mold/disease. So it's better to have fewer but bigger attachments than lots of little ones. Going directly through a trunk is not actually that bad and is about the same as having two non-through holes, but is usually unnecessary unless you want to attach things on both sides of the trunk. Its also a good idea to seal any holes with something like bees-wax. I put a food safe bees-wax based wood polish and raw bees wax (both from Bunnings) liberally on the threads of my attachment bolts to both lubricate (screwing in large threads to trees is HARD) and seal around the edges of the hole.

2. Tree trunks grow wider as the tree grows, they don't grow upwards. This means you need to give clearance for the tree to grow, and avoid attaching things directly to or encircling the trunk. They recommend leaving about 5cm clearance around the trunk. Because they don't grow upwards you don't have to worry about things growing out-of-level.

3. Trees move quite a bit in the wind. This movement is not necessarily that large, but it has enough force to shatter anything you attach to more than one trunk if you don't design it to allow for this movement. In general you can only have one "static" attachment trunk, and attachments to any other trunks need to be "dynamic" and allow movement.

The Nelson's Treehouse youtube videos and websites show their special Treehouse Attachment Bolts (TAB) and static and dynamic uplift arrestors for attaching to them with/without allowing movement. Unfortunately that gear is crazy expensive to buy from the states, and is probably overkill for most treehouses (those guys build tree-mansions with that gear). I made my own based on a bunch of online research using mostly stuff you can buy at Bunnings, with a handful of special bits from other online sources. I have photos and online OnShape CAD designs and will post a thread detailing them soon.

https://www.workshop.bunnings.com.au/discussion/comment/144095#Comment_144095

Hi @dbaarda

Thank you for sharing your list, those are all excellent points you made in your tree house building rules list. It's definitely worth keeping in mind that a tree is a growing organism and its best to provide allowance for it when it expands.

We look forward to seeing your tree house project begin.

Eric