Basic Information

Similar to climbing on rock or in a climbing gym, a toprope belay device can be used when building a tree house. This requires a fixed point setup at the highest point. Toprope belays are particularly suitable where the height level has to be changed again and again. The disadvantage of this method is that two people are occupied and only one person be climbing.

The most commonly used und recommended belay devices are:

  • semi-automatic Grigri fuse device (Petzl)
  • semi-automatic Smart (Mammut)
  • semi-automatic Lory (Bornack)
  • semi-automatic ID's (Petzl)
Securing Toprope

Background Information

Example: Usage of Grigri

The Grigri from the manufacturer Petzl is now available in various versions - all of them are so-called semi-automatic safety devices from the sport climbing sector. The device works similarly to a safety belt in a car. When the rope is pulled slowly the rope run is not blocked. On the other hand, a jerky rope pull in the direction of the climber activates a mechanism that completely blocks the rope. The automatic blocking only works reliably if one hand holds the brake rope. The Grigri therefore works on the all-or-nothing principle when securing a climber. In order to release the locking mechanism (for example to release a climber), the belayer must pull the lever on the Grigri towards him. To suppress the blocking mechanism for quick rope release, pressure must be applied downwards on the lever base. In both conditions the device does not brake the passing rope. To reactivate the braking mechanism, the belayer must release the lever or remove the pressure from the lever base.

In pioneer technology, the Grigri is very practical for securing people or for abseiling and can also be used to build pulleys that can be released slowly.

When lowering, the brake rope is led over the brushed lowering edge of the device. Then, the jaws are carefully unblocked with the guide hand by operating the lever provided. The braking hand now releases the rope in a controlled braking action, the strength of the pull being controlled by the unblocking lever. The Grigri is suitable for rope diameters between 8.9-11 mm.

Important notes for the Grigri:

  • The most common mistake when using the Grigri is putting the rope into the device in the wrong direction. Therefore, always test by jerking the rope leading to the preclimber to make sure that it is really stuck in the device.
  • It has often happened that only one leg of the Grigri has been hooked into the safety carabiner. It is essential to check that we have hooked the device in advance!
  • If you hold the Grigri in your hand and unblock it with your thumb, you run the risk that in case of a forward fall, following your natural reflexes, the Grigri will hold on to the device. However, the clamping effect of the Grigri is only guaranteed if the clamping jaw is activated by the brake rope. Therefore: Always keep your braking hand on the brake rope!

Grigri 2 and Grigri+

Grigri 2 and Grigri+ are further developments of Grigris. The most important advancement is a "panic function" (Grigri+) which prevents you from sliding down uncontrolled by releasing the brake lever.


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Funded by Erasmus+ "Youth in Action"

The website and the content was developed in the project "Treehouse Camps - a Method to Strengthen Key Competences and Integration in Youth Work".

Project duration: September 2018 - August 2021