Climb Safe: How to Extend a Rappel Device
Every year, without fail, someone is injured or dies in a rappelling accident. This July it was the easily prevented mistake of rapping off the end of the line. At this point, it seems a little useless to keep reminding people to tie some knots in the end of their ropes.

Every year, without fail, someone is injured or dies in a rappelling accident. This July it was the easily prevented mistake of rapping off the end of the line. At this point, it seems a little useless to keep reminding people to tie some knots in the end of their ropes.
So what else can we do to make rappelling a little safer? Besides tying knots and ‘closing the system’ around ourselves there are things we can do to make rapping safer and more relaxed. This can be a literal lifesaver in stressful multi-pitch situations, unknown rap routes or after a long tiring day.
A Good Time to Extend
The rappel extension is the standard method for rappelling in most guiding circles and a technique that would benefit many climbers on the recreational side. While an extension isn’t always necessary for rapping off a single-pitch at the crag, in nearly all tricky multi-pitch rappels it can mean the difference between fun and stress or even danger.
There are two main advantages to the extended rappel. It allows the auto-block (or Prusik) knot to be centered underneath the rappel device instead of being rigged off the leg loop. Even if there is really nothing unsafe about using the leg-loop, it has a tendency to pull one leg closer and closer to the rappel device if you spend any amount of time hanging on the auto-block. This can be a real pain if you have a lot of tricky gear to remove, ice-screws or have a long traverse to gain the next rappel station with already frayed nerves.
The other advantage to extending your device is it allows you to transition from rappelling to ascending quickly and safely when using a belay device with an auto-locking mode like the Black Diamond ATC Guide or Petzl Reverso. This is lifesaver if you find yourself rappelling a tricky decent for the first time or in stressful conditions that could cause you to miss a rappel station.
Rigging an Extension
There are a number of ways to rig a rappel extension and all seem to work equally well in my experience. While it is possible to use a Spectra/Dyneema sling I would suggest using a double length nylon sling or other ‘personal anchor system’ like Sterling Rope’s Chain Reactor due to the more durable nature of the material and the lack of redundancy in a tether. If you use a spectra sling creating redundancy is recommended.
Girth-hitch your preferred tether to your hard points just as you would a daisy chain. Then by tying overhand knots you can adjust the height of your rappel device and length of your tether. I prefer to have my device as low as possible while making sure that my auto-block cannot jam. The auto-block is then rigged off the belay loop with a locking biner. You now have an extended rappel combined with your anchor tether.

Transition to Ascending
To transition to ascending grab a cord from you harness and tie a Klemheist knot around both rappel lines above your ATC. You can tie an overhand in the cord to create a comfortable length for your foot loop.
Now attach a locking biner to the auto-lock attachment on your ATC. When you step into your foot loop attach the locker to your belay loop. You now have an auto-locking ratchet that can easily capture your progress as you ascend using your Klemheist.
Note: You must rig your rappel with the brake strand in the same alignment when using the device to belay off an anchor for this to work.
Ben Markhart works as writer and photographer when he’s not guiding for the Apex Mountain School in Vail, Colorado. You can find more of his work on his website www.benmarkhart.comor on Facebook: Ben Markhart Photography.
We have opted to use affiliate links in our gear reviews. Every time you buy something after clicking on links in our gear articles you’re helping support our magazine.