What type of rope do you need? That depends on the type of climbing you plan to do, whether sport climbing, big walls, alpine or rescue. One of the most versatile ropes is a 60-meter-long (196.8-feet) dry rope with a 9.8 millimeter to 10.2 millimeter thickness.
When shopping for a rope, it helps to know a little about rope anatomy. Most ropes have a kernmantle construction, consisting of a sheath and a core. The sheath is the protective, braided cover of the rope that protects the core and adds strength and shock absorption. Sheaths make up 30 to 40 percent of a rope's mass. The thicker the sheath, the more it resists cutting and abrasion.
The core refers to the inner twisted core strands of the rope. Filament is the thinnest thread that a rope is woven from, and twisted groups of four to six filaments make up yarns. Yarns are bundled together to make the core.
Here's the skinny on ropes:
- Workhouse singles have a larger diameter and hold up to lots of use. This rope is ideal for big walls, top roping (when a rope is secured to an anchor point at the top of the route before the climb begins) and extreme use. On the downside, it can be bulky and heavy to carry.
- All-round singles are the do-everything rope. They have average diameter, weight and fall ratings (a measurement of the stress applied to a rope if a fall occurs). They're ideal for sport, traditional and alpine climbing.
- Skinny singles are ideal for very long or difficult climbs because they're lightweight. On long routes when you're turning over many belays, constantly pulling in slack or in an alpine situation where you're coiling rope over your shoulder and using switching techniques to move back and forth up a long climb, the lighter weight can make a big difference in the long run.
- Half ropes, also known as a double rope, are two identical ropes used as a pair. They can run parallel through the protection using a twin rope technique, or you can alternate the "right" and "left" ropes through different protection points. They're good for long, wandering routes on rock, ice or alpine routes when you might need to rappel or retreat. (A wandering route is an indirect path to the summit, whereas a non-wandering route is more direct and vertical.)
- Twin ropes are a good two-rope option. They're lighter and less bulky than half ropes and good for ice climbs and straight non-wandering rock climbs where repelling is necessary.
- Static ropes are used in situations when you don't want rope to stretch, such as repelling, rescue and big-wall ascending, or anytime you're lowering, ascending or pulling a load up with the rope.