Author: Katy H.
The Grand Climbing Rope Buying Guide
Your rope is your lifeline and, when it comes to climbing, it's arguably the most important piece of safety gear. So, it makes sense to know what you need out of a rope. In this article we discuss the key features, decision points, and end uses when selecting your next rope.
How are Climbing Ropes Designed?
Climbing and most life-safety ropes, whether dynamic or static, use a kernmantle design which involves weaving a protective external sheath over a thicker core of twisted or braided yarns. The sheath is made of woven yarns and protects the core from abrasion. The core of the rope is made up of heavily braided or twisted strands that give the rope it's strength and dynamic properties (stretch). Chemical and heat treatments to the core and sheath fibres help to reduce internal friction in the rope when sustaining a fall, reducing water absorption, as well as improving handling, durability, and lifespan of the rope.
Rope Materials
Dynamic climbing ropes are almost exclusively made out of nylon. Static ropes may be made of Nylon, Polyester, HMPE (Dyneema) and Aramid Fibers (Technora, Kevlar), or a combination of those fibres.
Nylon
Nylon is selected for dynamic ropes because it has high stretch resistance (ability to rebound to normal size after being elongated) and shock resistance (ability to maintain strength despite withstanding high levels of sudden stress). When used in the core of static ropes, nylon provides a softer hand and energy absorption.
Polyester
Polyester is typically used in static ropes with minimal elongation under load. Polyester is more abrasion resistant than nylon, has very high UV resistance, is water-resistant, and low stretch. Some static lines have a Polyester sheath for abrasion resistance and weather protection and a Nylon core for handling, while other static lines built for use in high abrasion, wet conditions may be 100% Polyester.
Aramid
Above: Edelrid Swift Protect Pro 8.9
Aramid is a premium low stretch high strength fibre that provides extremely high breaking strength, excellent heat resistance, and high cut resistance for low weight. It is often used in rap lines. Aramid is water-resistant so useful in wet conditions. It is often combined with polyester or other fibres to compensate for its lower UV resistance. It has a very high melting temperature, but low resistance to repeated bending. Edelrid has recently launched new dynamic ropes incorporating aramid fibres into the rope sheath, providing increased cut resistance in narrow diameter dynamic ropes.
HMPE
HMPE, or high modulus polyethylene, provides the highest strength for the lowest weight. It is sometimes used in the core of static ropes to keep the rope small and lightweight while still strong. Most climbers will recognize this fibre as the white Dyneema in their slings or quickdraws. HMPE has a low melting temperature, but high resistance to repeated bending. It is an extremely slippery fibre, which makes keeping knots tied in it difficult. It is normally sold as pre-sewn slings and quickdraws, or with a nylon sheath to give it easier handling and knot-ability.
Length
Above: BD 8.9 Dry (80m), BD 9.9 Dry (70m), BD 9.4 (60m)
Length is one of the most important decisions you will make about your rope. If your rope is too short you could potentially climb into some dangerous situations, and if your rope is too long it can be annoyingly heavy or bulky to carry around and drag up climbs. Dynamic climbing ropes are most commonly sold in 60m or 70m lengths, with 80m and 100m lengths becoming more common, especially if travelling to crags with longer routes such as those found in Spain or Greece. 70m is the most common length to buy for Squamish as you will encounter some 35m rappels.
Often the ends of the rope will wear out faster, especially if lead climbing and projecting on the rope. Chopping the ends off your rope when they wear out is one way to extend the life of your rope, so buying a longer rope gives you enough length that it is still a usable length if you need to shorten it.
Diameter
Above: BD 8.9 Dry, BD 9.4 Dry, BD 9.9
There is a trade-off between lightweight performance and durability when considering what diameter of rope to buy. Durable ropes for new climbers, heavy top-roping sessions, or big wall climbing come in 9.8mm - 10.5mm. Ropes in the 9.4 - 9.7mm range strike a good balance between lightweight and durability for lead climbing sport and trad, and long routes. Lightweight thin ropes in the 8.7mm - 9.4mm range are great for long routes or hard red points but sacrifice durability. The reduced rope drag and weight of these ropes could make or break the send, but they should only be used by experienced climbers with proper handling and belaying techniques.
Stated diameter falls +/-5% from how it officially measures, so some ropes may feel “fat” or “thin” for a given diameter when compared to ropes from other brands.
Dry Treatments
Dry treatments help to reduce the amount of water your rope can absorb. This is designed to prevent the rope from freezing stiff when ice climbing or mountaineering. Preventing water absorption also helps to maintain the maximum strength and dynamic properties of your rope. The dry treatment can also maintain the handling performance, and extend the lifespan of your rope by preventing dirt accumulation. Some ropes will have a full dry treatment on both the sheath and core, while others may only have the sheath or core treated for the desired performance characteristic such as helping the rope to run smoother. As mentioned, dry treatments also help reduce internal friction in the rope when sustaining a fall because the treatment allows the yarns to slide overtop of each other as the rope stretches, which has a direct impact on the longevity of your rope.
UIAA Water Repellent
Above: Sterling Dry Rope
Due to various dry treatment technologies ranging in performance, the UIAA has developed a certification and standard test in which a rope may not absorb more than 5% of its dry weight. A non-dry rope can retain up to 50% of its body weight in water for comparison, and various dry treatments may still allow a rope to absorb between 20 - 40% of its dry weight. Ropes with the UIAA dry treatment standard are the highest performance dry treated ropes, which may be necessary for the conditions of the route or style of climbing, but they do come at a price premium.
UIAA Falls
The strength of a dynamic climbing rope is not measured in the same way as most of our other safety equipment; as a minimum breaking strength or MBS. Dynamic ropes are measured on how many standardized tests “falls” they rope can take before breaking. (4.8m drop on 2.5m of rope, over a 5mm radius curve, with an 80kg mass for single rope, and twin ropes used in pairs, 55kg for half ropes, etc, etc…)
When it comes to real-world daily performance, this fall rating does not translate easily. The tests for these falls are extremely severe, and taking even one UIAA “fall” on a dynamic rope is likely to leave you damaged. Your rope has the strength to catch dozens and potentially hundreds of average climbing falls during its lifetime, assuming that you use it properly.
Impact Force
The Impact Force is the amount of energy transferred by the rope to the climber, belayer, and onto the gear. It is an indicator of how well the rope absorbs energy (stretches) from a fall. Lower impact forces may be desirable for lowering the force in a fall on a marginal piece of gear, which is an important consideration when trad climbing but they will stretch more. Stiffer ropes may be preferred if a climber doesn't wish to fall as far due to rope stretch, such as in a top-roping scenario.
Sheath Percentage
This is a measure of how much of the rope is made up of the sheath vs the core. The thicker the sheath, the more abrasion resistant the rope tends to be. The trade-off is that ropes with a higher sheath percentage don't tend to handle as many UIAA falls. Climbers often prefer higher sheath percentages (e.g. >40%) on skinny dynamic ropes for added cut protection.
Weave
The weave of the sheath can affect the durability and handling of the rope. The tighter the weave the more durable a rope tends to be. However, ropes with a tight weave often feel “stiff” sooner, at which point they are not as pleasant to climb or belay with. Most sheaths have a two-over-two yarn design for maximum abrasion resistance, but some are built with a two-over-one or even a one-over-one twill design which reduces rope drag and improves handling.
Dynamic Elongation
This is the amount of stretch in the UIAA dynamic fall test. The range a dynamic rope can stretch is between 10-40% at maximum extension during the drop test. The higher the dynamic elongation, the farther you'll travel, and the higher your chance of potentially hitting something.
Static Elongation
This test is performed on dynamic ropes with an 80kg static mass placed on one end of the rope and is limited to a maximum of 10% elongation. A low static elongation could be beneficial for less rope stretch while working a route, or while top-roping.
Bi-Pattern & Halfway Marker
Above: Sterling 9.2 Evolution Aero (left), Sterling 9.0 Nano (middle), BD 8.9 Dry (right)
Most ropes these days come with a middle marker. There are also ropes that will change pattern at the middle point. This makes finding the middle of the rope significantly easier for communicating to the climber or when setting up rappels. A bi-pattern rope is more expensive, as the manufacturer needs to change the weave of the sheath midway through making the rope.
Dynamic Ropes
Dynamic ropes stretch in order to dissipate the forces generated in a climbing fall to keep the climber and belayer safe from injury. A dynamic rope combined with good belay technique softens the impact of the catch and prevents hard impact with the wall that can cause you to break an ankle or get whiplash. The rope type (Single, Half, Twin), the style of climbing it is being used for, and how it is being used, help to determine the characteristics you look for in a rope.
Single Ropes
Single ropes are designed to be used alone and are the most common rope type used in the rock climbing world. The main advantage of this system is that they are simple to use, and since the majority of rock climbers only use single ropes, they are familiar with proper rope management, handling and belaying techniques. Single ropes range from 8.5mm to 11mm in diameter. This symbol designates a rope as a single rope.
Half Ropes
Half, (aka “double”) ropes usually range from 7.5mm to 9mm in diameter and are used in pairs clipped independently to protection. They are designed to stretch one at a time to cushion the shock of a fall. If managed well, half ropes are useful on wandering pitches to reduce rope drag. They provide additional protection if one of the ropes were to be cut or damaged.
Half ropes also allow for full-length rappels when descending. Rope management is more difficult than a single or twin rope because the leader needs to make sure the strands don't get twisted around each other while alternating clips and the belayer will need to feed them out independently. Half ropes should not be clipped together to the protection, as this can result in higher impact forces onto the protection and climber. If shopping for half ropes, make sure to purchase two different colours, as this will be necessary when communicating things like “slack on blue!”, or “tension on red!”. The symbol used to designate half ropes will look like this:
Twin Ropes
Twin ropes, usually 7mm to 8mm in diameter, are used in pairs and clipped together into protection as if they were one rope. Their dynamic elongation is appropriate when they are used as a pair. If clipped alone they are too stretchy and unnervingly thin. Twin ropes add redundancy when there is a chance of cutting ropes (e.g. sharp equipment in ice climbing or icefall), and they are beneficial whenever you need to carry two ropes to descend. If you want a double rope system and don't expect wandering pitches, twin ropes can be the best option because they are lighter and easier to handle than half ropes.
Multi-Purpose Ropes
Ropes with multiple ratings have been tested and approved for multiple applications. Very skinny single ropes can be triple-rated meaning they have been certified for use as a single, half, and twin rope. It is also common to see double ropes rated with both twin and half rope ratings. Multiple ratings can give more flexibility of use. For example, a pair of triple rated single ropes can be very useful if you are climbing as a party of three in the mountains, and want to bring up two, second climbers at the same time. In this application, the lead climber can lead with two ropes clipping them either as a pair or separately and since the ropes are single rated it is safe to bring up the two, second climbers simultaneously one on each of the ropes.
Static Ropes
Static ropes have very little stretch, and should never be used for climbing when there is a dynamic fall (free-fall) potential. Freefall onto a static rope places very high impact forces onto the climber and their equipment, which could result in serious injury or worse. Static ropes are useful when rappelling, ascending, hauling or top rope soloing because there is less energy spent due to fight rope stretch. Static ropes can also be safer in certain applications because the rope doesn't chafe against the rock as much due to stretching. You can quickly wear through a rope if it is rubbing repeatedly over the same point, such as when you are ascending a fixed rope. Static lines 9.5 - 10.5mm in diameter are typical for ascending lines or top rope soloing, but smaller diameters such as 8 - 9.5mm might be preferable for hauling.
Rap Lines
Rap lines or Tag Lines are skinny static lines, usually 6mm-8mm, that are the lightest weight option for a second rope for rappelling. Since they are static, using them in combination with a progress capture pulley like a micro-traxion provides a fast and efficient method for hauling packs. The benefit is that neither the lead or the second climber needs to carry a pack on difficult pitches. Since they are very small they can be stacked into a bag at belays in windy conditions (when ropes can get blown and tangled) or even carried in the pack on easy terrain. While rap lines provide for full-length rappels, they shouldn't be climbed on to retrieve stuck ropes. One exception is the Edelrid Rap Line which has some dynamic stretch and is rated with UIAA Falls 2. This can give you some peace of mind retrieving a stuck rope. It is important to consider the difference in stretch when rapping with a dynamic rope and static rap line. Since the two ropes will stretch a different amount the two ends will be different lengths - check your knots!
Application of Ropes
In climbing, there are many reasons why we would use a rope. The majority of climbers can get away with only having one rope, but many climbers decide to have several different ropes for all of the different applications they might use them for. In this last section, we'll look at what kind of rope would be used for some common applications and why you would choose that rope.
Top Roping
For top-roping climbs, you'll want a single rope. Dynamic rope is the most common choice, but not absolutely required, as long as the belayer is attentive and there is no potential for a significant fall. A larger diameter rope will be more durable for the rigours of top-roping. Since climbers do not take large falls top-roping, a lower % stretch is safe and desirable since it can help to reduce fall distance. Look at how long the climbs are in your local top roping area, your rope will need to be at least twice this length.
Single Pitch Lead Climbing
The majority of ropes on the market are made with this in mind. For most climbing areas you will need a rope rated as a single rope. If you're looking for something to “project” climbs with, you'll probably be looking for something a bit more durable. Something in the neighbourhood of 9.5mm is a good balance between performance and durability. If you're looking to climb longer routes, something skinnier may be desirable to reduce weight and rope drag.
Multi-Pitch Climbing
When multi-pitch climbing, a longer rope isn't always better. The longer your rope is, the heavier it is, and the more time you will spend pulling up a rope between pitches. Sometimes having a bit more length can be good for linking pitches, but just because you can link pitches doesn't mean you should. Belay stances and rope drag often determine anchor positioning, as opposed to pitch length. Most multi-pitch climbs are established with a 60m rope in mind, but check the topo because modern routes may be designed to be descended with a single 70m rope, in 35m rappels. If you're trying to move fast and light and don't expect to fall often, a skinny rope is nice for its low bulk and weight. A 60 to 70m single rope that is a smaller diameter (around 9mm) is usually the best option for this application. Halves are also a good option especially if you're in loose or wandering terrain. Having the two ropes also means you can do longer rappels and share the weight of the ropes on the approach and descent.
Mountaineering
Weight is one of the most important factors to consider in an alpine climbing rope. If you want to climb on a single rope then look for something skinny (around 9mm or less) and ideally triple rated. This means that you can use the rope as a half, twin or single depending on the situation. If you want to share the weight with your partner then a pair of half ropes might be a better option. Not only do they allow you to share the weight during the approach, they will reduce rope drag on wandering routes as well as allowing for full-length rappels, saving time and energy during your descent.
Ice Climbing
All three types of ropes have their place when ice climbing, although this is the most common use of twin ropes. You clip both lines through each piece of protection, providing a backup if you were to cut one rope with any of the numerous sharp things attached to your hands and feet! These twin ropes need to be dry treated and tend to be very skinny (between 7mm-8mm). Many climbers rely on single ropes for ice climbing, as they use the same rope for other climbing pursuits.
Glacier Travel / Ski Touring
Recent developments in rope technology have provided some incredibly light yet strong ropes. Products such as the Petzl RAD line and Mammut Glacier Cord are examples of these. They are very skinny (around 6mm) and very lightweight. These hyperstatic ropes have extremely low stretch and are not designed to be used in a situation where you might take a dynamic fall, caught by a tight belay. On glacier travel, the friction as the rope cuts into the snow along with an unanchored belayer, will provide adequate deceleration to compensate for the lack of rope stretch. These ropes are not meant for lead climbing or any sort, they are however excellent for hauling, crevasse rescue and rappels. Bear in mind that your normal belay device will probably not work with these ropes due to their small diameter. Instead, you should check with the manufacturer to make sure you are using compatible hardware before heading into the mountains.
Top-Rope Soloing
For top rope soloing you can use a dynamic or static rope. With a static line, you are less likely to cause damage, and it will make positioning yourself on the wall significantly easier, due to the reduced elongation of the rope as you weight it. The heaver sheath of static ropes can also be better suited to taking the repeated grabbing of your self-belay device.
Conclusion
Buying a rope is an investment, and important to your safety and performance on the rock. We love talking gear. If you have any questions, give us a shout, send us a note, or come see us at the Climb On shop here in Squamish. We'll be happy to help find the perfect rope for you.
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