Treehouse Platform Construction
Building instructions and tips from real treehouse professionals!
The platform construction is one of the most challenging parts of building a treehouse: no matter what the treehouse will look like later, the platform must be securely anchored in the tree so that there is no danger and no one can come to harm.
We show you examples of how to build a 100% safe tree platform from our “Support Elements”. To ensure that the tree does not suffer from the construction even after 20 years, we use our Treehouse Screws as fasteners.
1. Small 1-tree platform
Our simple solution for small children’s treehouse, playhouse, viewing platform and hunter’s stand:
All you need are 4 x GTS Free with which you build a small triangular construction!
As the stainless steel bolts go straight through your wooden beams (without additional accessories), the GTS Free is only suitable for small decks:
- < 6 m² (65 ft²) in softwood
- < 10 m² (108 ft²) in hardwood
Minimum trunk diameter for two GTS Free opposite each other: ø > 30 cm (11.8 in)
- The platform should be centered around the tree.
- Reinforce your support beams around the GTS Free with fully threaded screws.
- Use lots of screws and wood glue or better PU glue to stabilise your lower triangular connection around the GTS Free!
- You are welcome to build a children’s playhouse on top of it, but it should be really small and light.
- A slide and a ladder firmly anchored in the ground strengthen your construction.
Is your treehouse tree still very small and young < ø 30 cm (11.8 in)?
There are good solutions for this too: The smallest possible diameter of a tree for building a treehouse (ø at the height of the attachment) is 25 cm (9.8 in). If your tree trunk is thinner than ø 25 cm, we recommend building the treehouse on stilts.
Variant 1: Offset the Screws
Offset the height of the screws on one side (at least 10 cm) – so they will not hit each other in the middle of the tree (see picture).
Variant 2: Triangle + Stilts
This solution is particularly suitable for trees that are very close to the property line and where the treehouse would otherwise protrude over the fence to the neighbour. You can build a larger platform with the supports set in concrete. Don’t forget the struts on your stilts, otherwise your treehouse will tip over towards your neighbour!
Remember that small, young trees still want to grow properly – plan your treehouse so that this is possible!
Do you want your platform to be bigger and heavier?
Then switch to our larger, black GTS Tree Bolts:
Instead of the upper GTS Free, you can use e.g. a GTS Friend + Static Support + Distance Rings: the longer shaft and the support give you more leeway for crooked trees, the load capacity is higher! Assembly becomes even easier.
For large vertical loads you can use the GTS Top in small trees – for this the trunk must be very straight! Often it is enough to install only one GTS Top.
Every project is unique – just combine the screws that fit your treehouse perfectly!
2. Medium 1-tree platform with wood struts
Another classic among the 1-tree platform constructions are wood strut support structures. The struts are very easy to prefabricate and assemble – with our Strut Support Safety, you can even adjust the height afterwards!
- Softwood < 12 m² (129 ft²)
- Hardwood < 16 m² (172 ft²)
The “Brackets” should be loaded as evenly as possible.
The trunk diameter for 4 GTS Side should be ø < 35 cm (13.8 in)!
Of course, you can also offset the height of the Bracket pairs so that the Tree Screws do not get in each other’s way (see above).
Variant 1 – wood struts screwed directly on the trunk
This is a quick and cheap solution for temporary treehouses.
Moisture can build up between the tree and the strut at the point of contact, and the strut can rot there. If your tree is still very small and young (< 40 cm), we advise against screwing wooden beams directly to the trunk – the trunk still wants to grow strongly in width and could be hindered or will simply push your struts away.
With thick, mature trees, there is nothing to stop individual struts being screwed directly to the tree. Use sturdy wood (oak, Robinia) and several ø 8 mm wood screws.
Variant 2 – Strut Support Safety
The advantages are obvious:
- You have more freedom during assembly (unevenness on the trunk is irrelevant)
- You can adjust the length of the struts afterwards.
- Not only that, but you give the tree more time to adapt to the new construction.
- The tree can simply grow around the small GTS Safety and continue to grow undisturbed.
- Waterlogging at the struts will not be an issue for the time being – you can do without expensive and difficult to work with oak and Robinia.
Variant 3 – With GTS + Support instead of GTS Side
This construction is also an absolute classic! The two parallel beams at the top form the basic framework for your platform. Depending on the load, you can freely choose which 2 GTS you use at the top.
Example – Loading a “Mix Construction”
1 – The front strut has to take a lot of compressive load: it should be strong; possibly braced in the middle with an intermediate strut sloping upwards; a second strut parallel would also be useful.
2 – The upper GTS bolts are pulled strongly in the direction of “arrow 2”: the left triangle wants to tilt. If we didn’t have an attachment on the right, the upper GTS would be very strongly loaded on extension! This is exactly why we have the upper screw on the right, which is now pressed into the tree and absorbs the tensile load.
3 – All the left-hand bolts together transfer the vertical loads into the tree trunk.
4 – Due to the large lever arm, there are also lever forces upwards: both the upper GTS and the strut are loaded in tension (green arrows 4, 5, 6). These parts should be extra bolted, glued and reinforced with angle plates.
Result of “example mix construction”:
In hardwood, this construction is possible with little load (no heavy, two-storey house!). In softwood, you should use larger GTS screws – a solid triangular construction would then also make sense! More on this below!
When planning your platform, think about where your loads will be transferred and what forces will occur at your connections. Also consider horizontal loads (storm) and rotational movements.
We have the right hardware for every treehouse project!
3. Large 1-tree platforms with triangular constructions
If you want to build a proper treehouse, stable “3D triangular constructions” are the best choice! If possible, use our Tree Screw GTS Allstar – especially with softwood, you are always on the safe side.
The advantages of triangle constructions with our “Brackets” and “GTS Allstar” are:
- The triangles are very stiff in themselves.
- The “GTS Allstar” can also take lateral, horizontal loads in softwood
- Cantilevered platforms are therefore easily possible
- On the long shaft you can position the support beams further out – the tree can grow undisturbed
Minimum trunk diameter ø > 45 cm
- Hardwood < 30 m²
- Softwood < 20 m²
Example – Large platform with 2 x “Triangle Set – 45° Heavy”
Instructions for assembling the tree platform:
The easiest way is to prepare the wooden triangles (white) on the ground, you can also divide them further.
- Mount the upper tree screw (GTS Allstar) and lift the triangle into position.
- Precisely measure the cross-beam and the Static Support and fix it to the screw.
- You mark the lower drill hole, swing the triangle on its side, install the lower tree screw.
- Then you push the entire triangle (incl. Distance Rings) onto both screws – finished!
Example – cantilevered platform with 2 x “Triangle Set – Vario Light”
Always take into account the greater leverage and rotational forces with one-sided overhanging constructions!
Install diagonal struts – these stiffen the platform and transfer the forces directly to the tree.
In this example, for example, the lower screw is heavily loaded horizontally. In hardwood, this is OK, as long as you don’t build a heavy treehouse on top.
In softwood, it is better to use GTS Allstar at the bottom – it can better absorb the lateral forces and rotational movements due to the large cylinder!
4. 2-tree construction with parallel beams and Dynamic Supports
The construction with parallel beams is simple:
- You can use the space under the treehouse freely
- Spans of up to 6 m are possible
- Thanks to the Dynamic Supports, your trees can swing freely
- Choose the right GTS Screw depending on the load and trunk diameter ø
- Also, good option for 3 or 4 trees
The beam dimension is easy to calculate (see photo). Note that your beam will be very heavy with large spans 😉
Tips for designing the platform:
- Mount the fixed bearings on the thicker tree, it swings less and is the fixed point.
- The treehouse (the main load) should be as central as possible above the beams.
- The main load should rather be on the side with the fixed bearings.
- Avoid lateral loads and large lever arms.
There are two simple solutions to support wide overhanging parts:
1. From below – Strut Support Safety or Strut Support GTS.
If you only need one strut and want to support smaller loads, Strut Support Safety is your choice.
If you need to support larger loads, you can use several Strut Support GTS on the shaft of our large GTS Screws (Allstar, Friend, Top)!
Attenzione Sensazione! Work on the moving side (with the Dynamic Supports) without Distance Rings – this way the struts remain somewhat movable and can absorb the movements of the construction.
2. From above – with a Cable Suspension
If the struts at the bottom bother you, you can also secure your platform from above. The advantage of rope suspension is that it is easy to assemble and adjust.
A stable branch fork or a twig where you can attach a tree loop is suitable as an anchor point. Alternatively, you can hang the rope on one of our Tree Screws.
Attach the steel cable to the wooden beam with a ring nut and carriage bolt and reinforce the platform construction there if necessary. Tighten the steel cable with a turnbuckle.
Alternative: Triangle construction – spread your wings!
With a triangle you bring your support beams far out and your platform becomes more stable! This construction is a good idea for trees on the property line, where the triangle does not interfere.
The following examples illustrate which supports you need (see floor plan):
- Both trees thick (ø > 50 cm), hardly any vibrations: Tree 1 – Static Supports.
- Triangle tree very thin (ø < 35 cm) vibrates in the wind), tree 1 thick (see photo): Tree 1 – Dynamic Supports, completely limited laterally with Distance Rings, Dynamic Supports can only move in the direction of tree 2, not laterally.
- Tree 1 thin, triangle tree thick: Tree 1 – Dynamic Supports limited laterally with Distance Rings.
5. 2-tree construction with triangles
A supporting structure made of triangles opens up many possibilities for the design of your platform. Cantilevered shapes and large base areas can also be realized in this way.
Assembly usually proceeds as follows:
- prepare the triangles on the ground
- fix the triangles in the tree (with our GTS Tree Bolts)
- screw your platform construction on top (e.g. 6 × 12 cm beams) – this can protrude over the triangles.
- Once the triangles and the platform level are firmly screwed together and stiffened, plank the platform with your floor boards
The trunk diameter for a triangle in a tree should be about ø 40 cm (14.8 in) for the lower screw.
Oh wind, oh wind – how do the triangles stay movable?
- The triangles have some play on the shaft of the GTS Screws.
- The wood of your platform construction will usually cushion the remaining movements.
If you want to build very high up, or in very thin, swinging-prone trees, you should consider a construction that can absorb these movements. For example, you can decouple the platform from your triangular cross-beam with “glide shoes”. You can buy PE-HD Sliding Plates for this in our shop!
6. Treehouse in 3 or more trees
Congratulations! With the knowledge from the previous examples, you are now ready to plan a tree house in several trees. On our page “Supporting Elements” you will find more useful details.
Finally, a few examples with several trees.
If you’re still not sure what you want your treehouse should look like, take a closer look at our article “Planning and designing treehouses”!
Just like every tree, every treehouse is unique! Take your time, make sketches, combine our products and design the perfect platform as the basis for your dream house!
Here again are the 5 most important rules for building a treehouse:
- Trees and their branches swing independently of each other in all possible directions.
- The tree wants to grow – give it room to do so: the trunk diameter ø increases by approx. 5 – 15 mm every year.
- Keep the balance: watch out for leverage and torsional movement
- Stiffen the construction with triangles, struts and diagonals!
- Distribute the loads as evenly as possible among the individual fasteners