Rope technology has come a long way since strands of reed were wound together to produce the first long ropes in Ancient Egypt. In the early 21st century there are several types of ropes that climbers use in the beautiful game. There are two basic types of rope you will come across in climbing scenarios; dynamic rock climbing ropes and static rope used for abseiling, rigging, fixed ropes and our close cousin sport SRT caving. In this short article I will attempt to clarify the range of dynamic ropes available today. These have diversified; way beyond the simple division of single and half ropes that I was brought up on. Each of the newer types have their own unique use in climbing, as well as a distinct set of strengths and weaknesses.
Choosing the right rope for your climbing activity saves you money and aggravation: ensuring your safety in knowing that you have the right equipment on hand when you're feeling all alone, hanging on the vertical side of a sheer-faced rock wall. When you're up there; on a climb, no thought is more comforting than the knowledge that you have the right rope securely fastened into your rock climbing harness.
Whether your passion is mountaineering, trad rock climbing, sport climbing or ice climbing, you need to understand the limitations of the types of ropes available to you for your particular style of climbing. Such are the advances in rock climbing rope technology that the manufacturers have fine tuned their products to meet the ever diversifying and always strenuous demands of climbing as a sport of many flavours.
There are five important technical characteristics of a rope that every climber needs to be aware of - the diameter, elongation, impact force, fall rating and the weight of the rope (grams per meter). In addition the less measurable qualities of flexibility and toughness are critical to your performance as you approach your technical limit on a particular project.
Climbing Rope Types
Workhorse Singles: 10.1-11mm diameter, 65-77g/m. The workhorse single is adequately protected against rough and sharp rocks and its larger diameter makes it easy to grasp for both the climber clipping gear on the lead and the belayer who is safeguarding him. Although a bit on the heavy side, it is perfect for top roping, redpointing sport routes and generally as a first rope. The 10 - 11mm climbing rope can endure severe and regular use making it ideal for activity companies, guides and outdoor static rope centres.
All-Around Singles: 9.5-10mm diameter, 60-64g/m. This is the preferred single rope for more experienced climbers. This type of rope has lower weight and thickness, but frequently a good fall rating. It is the most commonly used rope for the majority of sport climbers and is considered as the perfect rope for sport and trad climbing where the lines of the routes don't wander around too much.
Skinny Singles: 8.9-9.4mm diameter, 52-59g/m. The name says it all - the rope is thin and lightweight. It is the preferred rope if you plan to climb long routes but you should be aware that because if its reduced bulk and light weight, skinny singles do not have a great deal of durability against sharp and rough rocks. If you anticipate taking a lot of falls, it is prudent to make sure you are using a belay device that will match the thinner diameter and provide adequate friction. Modern belay devices such as Black Diamond's ATC series are well matched to this type of rope.
Half Rope: 8-9mm diameter, 41-53 g/m. Half ropes are used in pairs, with the two strands of rope being clipped into alternate gear placements. There are two facets to this style of ropework. The system is designed to reduce the severity of the consequences of a rope being severed due to a climber's fall or abrasion against a sharp rock face or edge, it is unlikely 2 will be cut at the same time and each is strong enough to hold a fall. Secondly, on routes where the line is complex and protection is not found in a straight line, using one rope on your left and another for gear placements to the right, significantly reduces rope drag. It is also the rope of choice when it comes to rappelling as you can tie the two ropes together to increase the rappel distance to a full rope length. However, the bulk and weight of half ropes make them more wearisome to carry than traditional single rock climbing ropes.
Twin: 7-8mm diameter, 37-42g/m. These really are the skinny ropes. Similar to half ropes but are lighter and less bulky. They provide the climber some of the same advantage of half ropes and at lesser weight to the climber. However they must both be clipped into each piece of gear, as they are not rated to survive a big fall as a single strand. Their fall rating is also much lower as there is far less nylon to soak up the energy of a high factor fall. This results in much greater damage every time they do have to hold a fall. Similarly to half ropes they also allow for greater rappelling distance but they can also be very slippery on abseil due to their lighter weight and small diameter. They demand extreme care and are not for the faint hearted.
There are quite a few considerations to bear in mind when choosing a climbing rope. As well as the details laid out above, you need to consider whether the climbing rope has sufficient flexibility, whether weight is a concern; can you easily tie knots with the rope and for winter climbers and masochists how does it behave in wet or icy conditions?
I hope the simple explanation above will help you make sure that you settle on the right rope for the type of climbing you will undertake. If you like challenges and you are highly active, then you will probably end up having several types of rock climbing rope for each of the specific climbing sessions that you do.