How to safety strap a chair to a tree trunk?

I am designing a chair, and I would like to strap it to a tree trunk. Trunk is about 18” diameter. I can’t screw into the tree because we rent our home, and there are no good horizontal branches to hang it from. I’m not trying to put it super high up the trunk. Maybe 4 feet up so you feel elevated but possible to get into easily with a step stool. The chair will be made of hardwood, so maybe 20lbs, and I’d like to overdesign to support a 200lb adult. The chair itself will be well built and solid, and I plan to install 4 heavy duty bolts (bolts not screws), one at each corner on the back of the chair. There will also be curved pieces on the back so the seat fits against the curve of the trunk. And then get 2 heavy duty ratchet straps and strap it to the tree. I will place vertical wood pieces between the straps and the tree to relieve pressure. (Internet says you should do this to prevent girdling the tree). How do I figure out what straps will work? (If this is possible) The straps need to do things, I think. Hold tension between the chair and the tree, and then maintain that tension with a grown man sitting in the chair. I thought about using climbing rope and tensioning with a pulley, but that will be challenging because the length of rope is short and you need a longer length to tension, I think. submitted by /u/Juxie [link] [comments]

Apr 24, 2025 - 06:58

I am designing a chair, and I would like to strap it to a tree trunk. Trunk is about 18” diameter.

I can’t screw into the tree because we rent our home, and there are no good horizontal branches to hang it from.

I’m not trying to put it super high up the trunk. Maybe 4 feet up so you feel elevated but possible to get into easily with a step stool.

The chair will be made of hardwood, so maybe 20lbs, and I’d like to overdesign to support a 200lb adult.

The chair itself will be well built and solid, and I plan to install 4 heavy duty bolts (bolts not screws), one at each corner on the back of the chair. There will also be curved pieces on the back so the seat fits against the curve of the trunk. And then get 2 heavy duty ratchet straps and strap it to the tree. I will place vertical wood pieces between the straps and the tree to relieve pressure. (Internet says you should do this to prevent girdling the tree).

How do I figure out what straps will work? (If this is possible) The straps need to do things, I think. Hold tension between the chair and the tree, and then maintain that tension with a grown man sitting in the chair.

I thought about using climbing rope and tensioning with a pulley, but that will be challenging because the length of rope is short and you need a longer length to tension, I think.

submitted by /u/Juxie
[link] [comments]