EUROPE'S FIRST ONLINESHOP
FOR TREEHOUSE BUILDERS
HOW TO: ATTACH
German Treehouse Screw GTS – versatile, safe and tree-friendly!
Whether it’s a huge treehouse, a small platform, a hunter’s stand or a swing beam – if you want to attach something heavy directly to a living tree, Tree Screws are the best solution!
1. What is a Treehouse Screw?
Without “Tree or Treehouse Screws”, modern treehouse construction as we know it today would not exist. The technology was first developed over 20 years ago by the American treehouse pioneers Charles Greenwood, Michael Garnier (Garnier Limb – “GL”) and Pete Nelson (Treehouse Attachment Bolt – “TAB”).
Based on the American bolts, we have further optimised our tree bolts and adapted them to the European market – may we introduce:
2. What makes Tree Screws special?
Tree Screws are extra-large screws specially designed for installation in living trees:
They can carry extreme loads of up to 8 tonnes.
The advantage over other attachment methods is that the wooden beams are kept at a distance from the bark and do not pinch off the tree (see picture). This allows the tree to continue to grow unhindered and to wrap the screw tighter and tighter year after year – a kind of artificial branch is created.
This makes tree screws the safest and most sustainable solution in the long run!
3. Why not use normal wood screws?
Ordinary wood screws and threaded rods with a ø < 40 mm should not be used for fastening in the living tree – this is for the following reasons:
- The material is not designed for the load: In contrast to normal timber construction, large swinging and twisting loads occur in the living tree (storms). This constant alternating stress can lead to fatigue fractures in normal screws.
- The tree grows in width with great force: wooden beams that are screwed directly to the trunk can modernise and break; screws can bend and break off.
- If the trunk is clamped over a large area and prevented from growing, predetermined breaking points can develop there.You can find more advantages and disadvantages of the different fastening methods here.
4. How exactly do Treehouse Screws work?
Our Treehouse Screw “GTS Allstar” has three segments:
- a: Coarse thread
- b: Cylinder
- c: Shaft (+ support + beam)
First, a precise hole must be pre-drilled. The coarse thread (a) and part of the cylinder (b) are screwed into the tree. This part of the screw transfers the load (F) of the treehouse into the trunk.
The other half of the cylinder and the shaft (c) are outside the tree. The supports including the support beam are mounted on the shaft.
Good to know:
The screw remains at the same height in the tree for its entire life, like an incised heart; it is only at the buds that the tree grows upwards.
If you wonder whether screws harm the tree, click here.
Around the screw, the tree forms particularly resistant wound and reaction wood. Over the years, the screw continues to grow around it and becomes an integral part of the tree.
5. Load capacity depending on tree and lever arm
The load-bearing capacity of our Tree Screws depends strongly on the wood properties of the respective tree. In general, it can be said that the screws in hardwood (oak, beech, maple, …) are about twice as resilient as in softwood (spruce, fir, pine, …).
The following table gives an overview of the load-bearing capacity of the individual screws – the values were determined during load tests:
The load capacity also depends strongly on the lever arm where the load is applied (centre of support + beam). The closer you move the construction to the tree, the higher the load capacity will be! For normal loads, we recommend about 10 cm distance between beam and tree.
The load capacity can be almost doubled with accessories!
6. Special features of our GTS
- We sell 6 different screw models: there is a suitable tree screw for every tree and for every load situation.
- Many accessories
- Low tool requirement: Thanks to perfectly matched products.
- European dimensions: screw and accessories were made up for the European market, i.e. metric dimensions, time-saving tool and spare parts procurement, no expensive special tools.
- Cordless working: Thanks to the further developed screw geometry and sharp tool cutting edges, pre-drilling is effortless with a strong cordless drill. Disturbing cables are now a thing of the past.
- Extremely high load capacity (in tests with Cable Suspension up to 8 tons vertical load)
- High safety & lasting stability
- Free thickness growth for tree
- Very low maintenance
- Proven fastening technology for over 20 years!
- 100% Made in Germany – Bavaria
- Lifetime guarantee on our large screws
Special Tree Thread: Specially developed coarse thread for tree, i.e. increased pull-out resistance (500 – 1000 kg) & optimum force flow.
Cylinder 74: The solid cylinder (ø 74 mm) transfers the loads safely into the tree trunk.
Top Seal: The increasing cylinder diameter seals the borehole, the screw fits snugly and tightly.
Tapered Transition: Over the years, the tree wants to overflow the screw. This process is facilitated by the tapered outer cylinder. The pull-out resistance of the screw increases and the flowing transition makes the overall appearance more aesthetic – like a branch.
Shaft 40: With a diameter of ø 40 mm, the shaft can withstand even the greatest alternating stresses – peaceful sleep is guaranteed.
Seamless: We do not use welded seams on our screws – our new process makes the screws indestructible!
Black KTL Coating: The environmentally friendly coating process ensures optimum corrosion protection and excellent sliding properties. Due to the black appearance, the screw disappears inconspicuously in the tree.
Here are a few example pictures of how to assemble a GTS:
- Screw in the screw
- Slide suitable accessories onto the shaft of the screw
- Mount the platform construction on the screw
You can find more information about the assembly here…