How do I choose a Rope?
Choosing the right climbing rope for your type of climbing requires some knowledge about various features manufacturers guarantee, and balancing features VS prices. Climbing ropes have to meet the minimal standards set by the European Union (CE) and can apply to pass also the higher standards set by the International Climbing and Mountaineering Federation (UIAA). On this article we will have a
general view on the ropes that are currently on the market and understand all the tests they have to pass, learning what those signs on the label mean.
First of all, let's look inside a rope! Climbing ropes are made of an internal kernel, composed of filaments woven in bobbins, and an external mantle, which is a protective sheath. While the mantle is vital to preserve the filaments from damage caused by abrasion, humidity and solar light, it is the kernel which does the thought job, holding
circa 70% of the tension.
Since 2010 Beal produces climbing ropes with their new design Unicore, which binds the sheath to the kernel (core), preventing slippage and dramatically reducing the possibility of falling when the sheath is cut under load.
UIAA guidelines for DRY ropes
The UIAA has released in 2014 the guidelines illustrating their new Water Repellent standard. In order to be labelled "Dry" by the UIAA, the amount of water a climbing rope can absorb should be less than 5% of its weight. "Dry" ropes must be treated with water-repellent products on both core and sheath. You can watch this video on how engineers at Mammut tests their ropes.
Under this new regulation, climbing ropes are now separated into 3 different categories:
- No water-repelling treatment at all
- Only Sheath treated
- Core and Sheath treated
Ropes on the market
This is just a list of the most famous ropes currently available. They are all single or triple-rated ropes. The price refers to the 70 meters model and can vary depending on where you buy and offers they may have.
|Producer||Model||Treatment||Diameter (mm)||Weight (g/m)||Sheath (%)||Dyn Elongation (%)||Falls||Price €|
|Sterling||Fusion Nano IX||Dry||9.0||52||?||33||6||280|
Why are climbing ropes dynamic?
What makes climbing ropes so special is their elasticity, and this is why they are called dynamic.
During a fall a climber is subjected to acceleration at first, and sudden deceleration at the end of the fall. The purpose of elongation is do absorb and dissipate the impact force produced at the end of a fall, avoiding the final recoil. Numerous researches proved that the max impact force a human being can tolerate is about 15 times one’s own body weight. This means that a person weighting 80 kg can tolerate an impact force not higher than 12kN. Ropes should thus be enough elastic to dissipate the impact force that passes 12kN.
Click here to read what is the difference between Kilograms and Newtons.
What diameter should my rope be?
In the last 20 years, thanks to new materials and manufacturing techniques, the diameter and weight of climbing ropes have drastically diminished. The majority of climbing ropes on the market have a diameter smaller than 10mm. Thin ropes are appreciated for their ease of use, but they wear faster.
Diameter always comes in relationship with weight, and when buying a rope it is important to know both measures. When comparing two ropes of the same diameter for example, we should pay attention to their weight too. The label on a new rope should show both measures in grams per meter (g/m).
Watch out for misconceptions: while a thick rope is not necessarily safer or stronger than a thinner one, a thinner rope does not necessarily weight less than a thicker one.
When choosing what rope to buy, pay attention also to which belay device you and your climbing partners will be using. Some devices can only work with thick ropes, while other are designed for new and thinner ropes.The old GriGri for example does not accept ropes thinner than 10mm, while the MicroJul works best with 7mm ropes. Have a look at our page dedicated to Belay Devices to understand more on them.
What is the difference between Single and Half rope?
Single ropes are used for leading and top-rope climbing. Single ropes are are the most resistant and long, and thus can be used one at the time, to belay a climber or to rappel. Single ropes come in length of 60, 70 or 80 meters. While in countries like England it is hard to find lengthy climbing routes, it is vital to have at 70 meters rope in Sardinia, as many problems are 35 meters high. Single ropes' diameter varies from the old 11mm to the actual 8.6mm.
Half ropes must be used in pairs. They are normally used for multi-pitches and trad climbing. Apart from double security, half ropes allow climbers to rappel faster, using the entire length of the ropes, descending 50 or 60 meters instead of 30. The diameter of half ropes is generally smaller than single ropes, and varies from 9mm to 7.3 mm.
Knowing that these ropes can only be used in pairs, we recommend buying them in pairs. This is to make sure you are always using a good pair of ropes and not recycling an old one in rough conditions.
A pair of half ropes should have the same length, to prevent falls when rappelling or other similar incidents. It helps to have ropes of the same diameter, and it is recommendable to have them in different colours.
It exist also another kind of rope, twin ropes, which is now disappearing from the market as replaced by single ropes. Although they are thicker than half ropes, they must be used in pairs and clipped together on each quickdraw.
More details on ropes
To pass homologation by European Norms, climbing ropes should not break under a steadily pulling before reaching 18kN. A second test adds an eight-figure know. Knots can limit the resistance of a rope up to 50%. When pulled steadily with an eight-figure knot, a rope should hold up to 12kN.
Each rope’s label must state the minimum number of falls it is guaranteed for. Single ropes must withstand at least 5 falls from 5 meters and fall factor 1. Single ropes are tested with a mass weight of 80kg, while half ropes are tested with a mass weight of 55kg. As stated before, the impact force at the first fall should be lower than 12kN for single ropes and 8kN for half ropes. Tests are repeated at 3 minutes intervals.
Although European (EN892) and UIAA Standards require only 5 falls, manufacturers usually guarantee at least 8 falls.
Extension during the first fall
European Standards demand that at the end of a 5 meters fall with a mass weight of 80kg a rope should not extend 40% more than the initial length.
Extension under load
To check the extension under load an 80kg weight is attached to the end of a rope. When the rope is pulled up, it should not extend more than 8% of its initial length for single ropes or 10% for half ropes.
Although elongation is the main characteristic for climbing ropes, an excessive elongation makes it much harder to perform certain safety manoeuvres. It is thus necessary to create ropes which could absorb the impact force with the lesser elongation possible.
To test the behaviour and flexibility of a rope, manufacturers make an overhand knot under a 10kg load. The internal diameter of the knot should not be less than 1.1 times the diameter of the rope.
These are the standards that allow a rope to be put on the market. Nonetheless there are many other aspects that are not regulated, such as manoeuvrability on rain of frost situations, the resistance of the kernel against a sharp hedge, the ease of movement inside belay devices of karabiners, the tendency to get knots etc.
 If falling head-up. In case of head-down falling the impact force is reduced to 5 times one’s own body weight.
 Max Force is measured in Newtons, multiplying body-weight times 15 (1Kg equals 9.8 Newton) F= 80*9.8*15= 11760 Newtons (rounded to 1200daN, or 12kN )
 CE and UIAA norms have established that the Kernel cannot move more than the 2% inside the Mantle.
 Edelrid Corbie – single rope – Diameter 8.6mm, Weight 51g per metre. (Updated May 2015).
 Beal, Gully - half rope - 7.3mm in diameter and weighs 36 grams per meter (updated may 2015)