Klemheist knot

In a klemheist the wraps lie in a spiral around the rope. The lower end of the loop runs through the upper end and comes out pointing down. When you pull on this end, it drags the upper end down with it, and the spiral tightens, like a spring that is squeezed and twisted at the same time. The wraps then press on the rope and create friction.

Because the pull comes from one side only, the knot is directional. Pulled the other way, the spiral does not tighten but rather loosens, and the knot can slip. This is not a flaw but part of its design – you just need to know it and orient the knot accordingly.

A good klemheist has several wraps lying close and tidy side by side without crossing. At the top you can see the upper end of the loop, with the lower end passed through it; this end then points towards the load. With webbing, the material should lie flat and untwisted, otherwise contact area is lost.

To set it, push the wraps together and pull the emerging end firmly in the direction of the load. Then check: does it grip under load? Does it slide upwards when unloaded? Always test with exactly the material you will use, because wetness, dirt and different ropes change its behaviour noticeably.

The most common mistake is the wrong loading direction: the knot is tied so the emerging end points upwards while the load pulls down. Then it slips. Loose or crossed wraps and too few wraps for a slick or wet rope are just as critical.

If a friction hitch slips under load, friction creates heat that can damage synthetic fibres. That is why testing before use matters so much – slowly and in a controlled way, not with a jerk. If it slips even a little in the test, add a wrap or use a different combination of cord and rope.

The klemheist makes sense when a load clearly pulls in one direction only, for example a tie-out that always pulls down at an angle. Its special advantage: it also works with webbing, where the prusik does not do well. It is also usually easy to release and slide.

Where the direction of pull can change, a prusik is the better choice because it grips both ways. This page is not a guide to self-belay for climbing, abseiling or rescue. Life-safety use only after proper training with certified equipment.

Hang a rope from a hook or branch so that it hangs straight down. Tie a klemheist with a loop of accessory cord and a second one with a piece of webbing. Pull carefully down on the emerging end by hand and watch how it grips. Then deliberately tie it upside down and see how it slips.

Afterwards compare it with a prusik on the same rope. You will quickly notice which knot suits which job. Practise until you recognise the right direction without thinking – with this knot, that is the most important skill.