Top Rope Belay Setup Overview

The climber and belayer must wear a harness designed specifically for rock climbing. The harness should fit snugly above the hips, with the buckles for the waist and leg loops doubled backed. Climbers are also required to wear shoes designed specifically for rock climbing. If the climber is wearing a helmet, it should be properly fitted and secure.

Climbers should know the components of the harness they are using

The harnesses that the wall rents out are comprised of simple webbing straps sewn together, incorporating (the color refers to the picture on the right):

  1. Self-locking buckles which should be doubled back
  2. A blue or black vertical belay loop, for clipping carabiners to
  3. Two blue horizontal tie-in loops, also known as hard points, for tying rope to

Setting Up the Belay

The belayer’s strand of rope is threaded through the belay device according to the manufacturer’s specifications and attached to the belayer’s belay loop on their harness using a locked carabiner. 

Tube style and Assisted Braking devices are both acceptable for top rope belay at indoor climbing gyms. 

For a basic tube style device, feed a bight of rope through either opening and clip both the bight and device’s keeper loop, with the brake strand feeding out of the bottom of the device. Once clipped, there should be no twists in the system or stands wrapping over each other. Verify the carabiner is locked by performing a squeeze test.

Consider an Anchor – A ground anchor is not required for most climbing at the climbing gyms, but should be considered if the climber outweighs their belayer by 20 kg or more. To use the fixed ground anchors, attach an additional locking carabiner to your belay loop, below the belay device, and then clip to a loop on the anchor so that it is relatively taut. Ground anchors are worth considering, too, whenever you’re forced to belay in a place that less than ideal: where you have an obstruction between you and the wall. 

Close the system by tying a stopper knot in the end of the rope. This ensures your end of the rope will never pass completely through the belay device, dropping the climber. 

Set up the belay device by sliding a bight of rope through the tube closest to your dominant hand. Though many belay devices are symmetrical, some have a grooved inner surface on one side of each tube: This provides additional friction if needed to belay a heavier climber or to belay with a rope that’s thinner or slicker than normal.

The climber-rope side of the bight, which goes up to the anchor and back down to the climber, should always be on the top side of your belay device.

Attach a locking carabiner, which must pass through the bight and belay-device cable, as well as your harness belay loop. To avoid stressing the cable on your belay device, make sure the rope bight doesn’t cross over the cable. Lock the carabiner.

Tying in the Climber

Choose the strand of rope closest to the wall, to keep the two strands from rubbing against each other. The climber needs to be attached to the rope with a solid connection that cannot come undone during the climb. 

At the climbing gym we require the climber to tie in with a Figure 8 Follow Through, a knot which can withstand a great amount of load and yet be untied relatively easily after the climb. 

Follow the harness manufacturer’s specifications on where the knot is tied, typically through both tie-in points. The knot should be tied within 15 cm of the harness and tightly dressed. The remaining tail must be a minimum of 15 cm long. Tying off the extra tail is not required for safety, but may be done to keep it out of the way.

How and why a belay works?

The skill of belaying is one of the cornerstones of climbing safety. Belaying is the technique of holding the climbing rope for a climber so that they are safe if they fall off the rock, as well as preventing them from hitting the ground if they take a leader fall or a fall while top-roping. The word belay was originally a nautical term that described a technique for securing a sailing rope to a post or spar on a ship. The same word was applied to the climbing technique of one person securing a safety rope for another person climbing, with the post being either the belayer’s body or a  belay device and locking carabiner.

Belaying is an Essential Skill

Photo by

The belayer is the person who establishes a belay by holding the rope. This turns a climbing  rope into a safety tool rather than what the great climber Royal Robbins once called “a lethal weapon.” Belaying, while sounding rather complicated, is actually an easy climbing skill to learn and to become a good belayer mostly requires lots of practice.

kN Ratings – Top Rope Fall Forces

Most lead falls have a fall factor of 0.2-0.7 and generate 2-5kN of force on the top piece of gear.

When top-roping, the distance fallen is minimal, therefore the fall factor is near zero. The force on the anchor will be the weight of the climber plus part of the weight of the belayer (around 1kN of force).If there is slack in the system, the force will be a little higher, but still significantly less than the typical forces on gear during a leader fall.

Belay technique PBUS with ATC 

This section covers how to belay with an ATC (Air Traffic Controller).

Belaying with an ATC involves knowing how to:

  1. Set up the ATC belay device
  2. Belay with the PBUS Technique
  3. Lower the climber with the ATC belay device
Photo by Petzl

Top Rope Belaying with the PBUS Method

Our recommended top rope belaying technique for both GRI GRIs and ATCs is the PBUS method, which is a four-step process of Pull, Brake, Under, Slide. 

Pull: The pull is a simultaneous action of pulling with both your guide and brake hands in harmony. The motion will consist of gently pulling down with your guide hand (seen as the left hand in the photo) and outward with your brake hand. These motions are to be done simultaneously so that extra slack doesn’t enter the system. 

Brake: Towards the end of your pulling motion, the brake hand should immediately go down towards your hip into a brake/locking position. This pull-to-brake motion should be fluid and in the shape of a slight curve.

Under: With your brake hand in breaking position near your hip, take your guide hand and place it under the brake hand.

Slide: With your guide hand now under your brake, slide your brake hand back up toward the belay device, ensuring that it never leaves the rope. After sliding, return your guide hand to the climber’s strand of the rope, ready to repeat the process. 

Belay technique PBUS with a gri  gri

The basic technique of PBUS remains the same but here are some important factors to keep in mind when using a gri gri. Here is what not to do: Note that the use of incorrect belay technique is the primary risk factor in an accident, especially when the belayer is surprised by a fall. If you recognize yourself in any of these illustrations of incorrect technique, adopt the technique presented at the beginning of this paragraph.

Holding the climber side of the rope
Incorrect placement of the index finger
Holding the gri gri with the entire hand
Giving slack without holding the break side of the rope