In this combination tech tip/gear review, Broad Beta's technical team downloads on fabrics for synthetic climbing pants. And remember, if you have any feedback or tips you'd like to see next month, send us an email at email@example.com
Fabrics for rock climbing pants have not changed radically in decades. Here are some simple things to understand that will help you choose a pant that’s right for your intended uses. Fit is the most critical in a pant and fabric makes a big difference in how a pant fits, in addition to its performance and durability.
This review is focused on lightweight synthetic climbing pants, as they are the most functional for multi-pitch climbs when the weather might go south. That said, many of us wear cotton on long hot routes when we know it’s not going to rain. We’ll review those options soon.
Synthetic fabrics are not all created equal. The two main things to pay attention to: the amount of spandex (stretch), and whether it is a double weave or single weave fabric. There is two-way, four-way stretch and mechanical stretch and stretch derived from adding spandex (otherwise known as Lycra or elastane). Stretch adds comfort, makes it easier to fit different body types and gives us the flexibility we need for heel hooks and mantels.
The more spandex, the more stretch, but often less recovery, meaning pants will bag out and need a wash for them to come back to their original size. Spandex adds weight and absorbs moisture, so the more of it, the longer it takes for your pants to dry. The heavier/warmer the pant, the less spandex you want (up to 10% is usually the most) for good recovery and quick dry time. In the lighter pants we’re reviewing here, up to 15% can still dry quickly since the fabric itself is so thin and light. Mechanical stretch is when a fabric is essentially ‘kinked” to produce stretch without any added spandex. This dries the fastest but does not provide enough stretch in a climbing pant, hence the added spandex.
Stretch woven is just what it says, it refers to the fact that the fabric is woven, not knitted. Knits use one fiber/yarn and inherently have lots of stretch. Wovens use more than one fiber and are more durable, more wind and water-resistant and hold a Durable Water Repellent (DWR) finish better and longer than, say, knitted leggings. There are single weave and double weave stretch woven fabrics. Single weave essentially means a fabric will look and feel the same on the inside as it does on the outside. It’s simple and functional in very lightweight synthetic pant fabrics. (Mammut and OR use single weave fabrics, Arcteryx uses a very light double weave).
Double weave stretch wovens have a different feel/look on the inside of the pant than on the outside. They generally have a softer and more open weave on the inside and a tighter, smoother weave on the outside. This creates a push pull effect for moisture to move to the denser outside faster so you stay drier on the inside. It also creates a tiny modicum of warmth against the skin that helps the pant feel comfy and a stitch warmer than a single weave making them work really well from cool pre-dawn starts to warm afternoons in the sun.All the pants we reviewed here are made with high quality stretch woven fabrics and most have a DWR finish to ward off light rain. These are all considered “softshell” pants but on the lighter side of what you may identify as softshell in other forms.