How to Choose a Climbing Rope
As with most equipment, selecting the right climbing rope is going to depend on your personal needs and uses. Different styles of rope are better suited for different types of climbs.
There are many things to take into consideration when selecting a climbing rope; diameter, length, static vs. dynamic, dry treatment, bi-pattern, impact force, elongation... the list goes on. Here we will take a look at key factors such as construction methods, and go into detail about different types of climbing ropes. We will also touch on how they test and standardize rope safety ratings, so you will know how to choose the climbing ropes that are best for you.
Dynamic and Static: The Difference
Dynamic Ropes
A dynamic rope is designed to stretch or elongate when weighted. This reduces the impact force exhibited on the climber and their gear when taking a fall. High impact forces will wear you and your equipment out faster. Due to its ability to handle high impact forces, this type of rope is designed to be used by climbers.
Static Ropes
Unlike dynamic rope, a static rope does not stretch when bearing load. These ropes are intended to be used when building anchors, hauling loads, and rappelling. This type of rope should not be used as a climbing rope because it will not absorb any forces in a fall scenario and could lead to serious injury.
Climbing Rope Terms
Diameter
Modern climbing ropes range anywhere from 8.0mm - 10.5mm in diameter. Large diameter ropes are heavy but very durable, making them a good choice for top-roping. Skinnier ropes are light and have low impact forces, making them best suited for alpine, ice, and hard sport on sights.
Length
Ropes come in a variety of lengths from 30 meters all the way up to 80 meters. Climbing ropes are often 60 or 70 meters in length.
Core
The core of a rope is comprised of individual yarns which are bundled into ply's. The ply's then get bundled together to form the core. The core is where your rope will get a large majority of its strength and shock absorption from.
Sheath
This is the pretty, colorful face material you see when looking at a rope. The main function of the sheath is to protect the core. The thicker the sheath, the more protection it will provide, increasing overall durability of the rope. While the main purpose of a sheath is to protect, it does provide a small degree of strength.
Breaking Strength
The breaking strength of a rope is measured using kilonewtons (formulated using mass, length, and speed) and represents how much force a rope can withstand before breaking. Dynamic ropes have a slew of other complex statistics in addition to breaking strength. Those are outlined in the UIAA Fall Test section below.
Types of Rope
Single Ropes
Single ropes are the most popular type of climbing ropes. They are used by themselves and are suited for top-roping, sport, trad, multipitch, and ice climbing. A pretty well-rounded, diverse rope.
Double Ropes
Double rope systems utilize two climbing ropes. They are best suited for multipitch climbing on rock and ice. The two double ropes systems are twin ropes and half ropes:
Twin Ropes
Twin ropes are designed to be clipped simultaneously into each piece of protection. The advantages are greater sharp edge protection, lower static elongation, and full length rappels. Disadvantages are rope drag and higher impact forces. Twin ropes are not to be clipped into protection independently, always use them in pairs.
Half Ropes
Half Ropes are designed to be clipped alternately into each piece of protection. The advantages are sharp edge protection, significantly reduced impact force, and full length rappels. Disadvantages are difficult rope handling and higher dynamic elongation. Double rope systems are great for multipitching in parties of 3.
Dry Treated Ropes
Dry treatments have many positive benefits to a climbing rope. A dry treated rope will absorb far less water when exposed to wet conditions, making it weigh less, dry faster, prevent icing in freezing conditions, and retain its dynamic properties.
A rope can be treated either on the sheath alone or on the sheath and core. Because the sheath is taking a majority of the abuse, the waterproofing on a sheath only treated rope can wear off leaving the core exposed to water.
A double dry treatment not only keeps water out, but also prolongs the life of a rope by keeping dirt particles out, and minimizing the amount of friction the core of the rope experiences during a fall. Dry treatments often cost $50-$75 more but are well worth the cost.
UIAA Rope Standards
UIAA stands for: Union Internationale Des Associations D’Alpinisme. The UIAA Safety Commission works closely with the industry to develop standards to minimize accidents caused by equipment failure. A certified piece of mountaineering or climbing equipment carries a UIAA Safety Label, which indicates the equipment’s compliance with UIAA standards. All of our climbing ropes must pass UIAA safety standards.
Fall Factor
The fall factor is calculated by dividing the distance of a fall by the amount of rope that is out. A fall factor of 2 is the worst-case scenario. This happens when a leader falls before placing any gear above a belay and falls past the belay.
Number of UIAA Falls
This is a measure of a rope’s ability to absorb energy in a harsh fall scenario. An 80Kg mass is dropped 5 meters with 2.8 meters of rope out to create a fall factor of 1.7. The number of UIAA falls a rope can withstand before failing is an indicator of overall durability of a rope but by no means indicative of the number of “realistic” falls a rope can withstand.
Impact Force
A measure of the force exerted on a climber and their gear during a UIAA test fall. Inversely related to dynamic elongation. More elongation equates to a low impact force. Balance must be met between elongation and impact force, as the UIAA puts a maximum of 40% dynamic elongation as its standard.
This measurement will affect day-to-day performance of your rope more than the number of UIAA falls. Lower impact forces are desirable for trad, alpine, and ice climbing where protection might be marginal. Lower impact forces will put less stress on you, your gear, and the person belaying.
Dynamic Elongation
This amount of stretch that occurs during a UIAA test fall. Higher elongation equals longer fall and lower impact forces. Lower elongation equals a shorter fall with higher impact forces. Less elongation is desirable for sport climbing where you don’t want to fall as far--especially when a fall close to the ground is more likely.
Static Elongation
The amount of stretch that occurs when a 176lb or 80Kg mass weights the rope. Less static elongation is desirable for top roping, lines used for ascending, and glacier lines.
Sheath Slippage
A measure of the amount the sheath separates from the core. 0% is desirable and is the norm for the majority of modern climbing ropes.