Which DWR is Best? The Future is Fluorocarbon-Free Bikepacking Gear
April 19, 2020
In 1998 a lawsuit started that would eventually lead to the 2016 ban of long chain perfluorochemicals (PFCs) used in US manufacturing. This ban affects a broad range of products including carpets, non-stick cookware, and your outdoor gear. PFCs shed water and stains exceptionally well, and for outdoor gear they are most commonly used for the durable water repellent (DWR) coating on fabric. The long chain variation of PFCs that have at least eight carbon chains (known as C8) are the targets of the 2016 ban as these chemicals have been determined to be carcinogens and toxic to our environment. Despite this ban, it’s estimated that 98% of Americans have PFCs in our blood and that they continue to damage our health and environment.
Introducting Smartrepel® X-Pac
After the ban, responsible outdoor gear companies transitioned to a different PFC that has a shorter carbon chain, a 6 carbon molecule termed C6. Today, almost all of your X-Pac fabrics use this C6 DWR. While it is still a PFC, this C6 alternative breaks down faster and is not as persistent in our environment. Is C6 safer compared to C8? Definitely, but that doesn’t mean its safe in general. The switch to a shorter-chain PFC is a step in the right direction, but its not our safest option.
So which DWR is best? The final solution for outdoor gear seems to be nothing short of PFC-free DWRs, also known as C0 DWRs. Last Monday (April 13th, 2020), Advanced Textile Source published a press release declaring the imminent ban of C6 in Europe. The PFC-free advocacy in Europe combined with the influence of a few progressive, US apparel companies has created an opportunity for Rockgeist and our customers.
We are happy to announce that for the start of 2020 we have been using X-Pac that is made with a natural based, PFC-free DWR. This innovative DWR is created by Switzerland-based chemical company Archroma, and is named Smartrepel®. Unfortunately, as a small cottage gear company, Smartrepel X-Pac is difficult to source for us. Availability is dependent on the purchasing power of large European companies and for the moment we can only offer Smartrepel in VX-21 Black X-Pac.
**UPDATE** As of Aug 2022, Rockgeist now offers various PFC-free (C0 DWRs) fabrics including XPac’s Cotton Duck series, RX series, and Ultra VX-40. EcoPak’s offerings are also PFC-free.
Does DWR matter for Bikepacking?
One of the largest obstacles in moving away from PFC-based DWRs is that alternative DWRs don’t perform as well. However, those arguments were mostly voiced from apparel manufactures, where “next-to-skin” performance is crucial. When a DWR fails and a jacket “wets out” there is significant discomfort and performance loss.
But what about for bikepacking gear? In our opinion, DWRs of any kind (C6 or others), do not contribute to a significantly better bikepacking product. Bikepacking gear is not next-to-skin and sees use and abuse different than jackets and pants. It’s also important to note that when X-Pac wets out, it still maintains its waterproofing. X-Pac is waterproof not because of a DWR coating, but because of a dedicated layer of material in its laminate makeup.
Take a look at the photo below. We argue the world’s best DWR on that framebag would not improve this bikepacker’s experience. With no DWR the bags might absorb more mud/water and weigh more, but in our opinion it’s an insignificant amount and not worth the environmental cost. And honestly, 6C X-Pac never won us over to begin with. If you’ve tested the water shedding ability of your traditional C6 DWR framebag after a season of hard use and sun exposure, you’ll be less then impressed.
Durability of Smartrepel X-Pac
Despite the questionable utility of DWRs in bikepacking, from the testing we’ve done (including over 5 months of sales and use at time of writing) we have seen no discernible DWR differences between Smartrepel and C6. In fact, our Smartrepel is coated on a base fabric that is more abrasion resistant than its C6 equivalent.
The VX21 Black Smartrepel we are using has a nylon base that gets an additional step of applied heat and pressure. As a result, the nylon fabric slightly melts and mats down the fiber ends creating a “wet” or shiny look. This process increases the abrasion resistance, which is arguably the most important material property for bikepacking gear.
Are there other framebag fabric options that are PFC-Free?
Yes, the most notable one being Ultra PE fabrics. Ultra PE fabrics are not only one of the most durable fabrics used in the outdoor industry but it’s also completely free of any DWR. This is because of the inherent nature of the fibers that make up this fabric. These fibers are termed Ultra High Molecular Weight Polyethylene (aka Ultra PE) and consist of long carbon chains saturated with hydrogen atoms. This unique and simple chemical make up of Ultra PE repels water so well no DWR is needed.
Unfortunately this does not mean all Ultra PE fabrics are DWR free. For example, Dyneema fabrics (a brand name Ultra PE fabric) are often composites, meaning they are mixed in with other fabrics, or laminated to traditional fabrics. A good example is our 2.92 Dyneema hybrid fabric; the outer Dyneema face is DWR-free but it’s laminated to a polyester backing that does have DWR coating.
**UPDATE** As of Aug 2022, Rockgeist now offers various PFC-free fabrics including XPac’s Cotton Duck series, RX series, and Ultra VX-40. EcoPak’s offerings are also PFC-free.
So where do we go from here?
Rockgeist we will prioritize ordering fluorocarbon-free (C0) fabrics and will no longer be re-ordering C6 DWRs. However, not all fabric options are available in a fluorocarbon free finish and this DWR transition will have to be propagated by the larger outdoor brands with buying power. You can help encourage this transition by supporting companies that are using C0, PFC-free materials in their gear. This not only includes bikepacking bags, but also your jackets, pants, and even the down in your sleeping bag.
If a product isn’t labeled with the type of DWR used, ask the company what they are using and if it’s fluorocarbon-free or PFC-free. If you shop at fabric suppliers for DIY projects ask them if they can source PFC-free fabrics. Like many industry changes, they often happen the fastest if they are driven by consumers.
Dive deeper into the DWR story with these articles:
The Lawyer Who Became DuPont’s Worst Nightmare. New York Times. (2016)
Hidden in Plain Sight; Poly-fluorinated chemicals (PFCs) in the air of outdoor stores. Greenpeace. (2016)
C6 ban expected in the EU. Advanced Textile Source. (2020)
Our DWR problem. Patagonia (2016)
You are Being Poisoned. Blue Ridge Outdoors. (2019)
I do not really get it for bike packing packs. Why use any DWR. Why not just coat the fabric with a safe waterproofing treatment so the fabric does not need a chemical DWR that breaks down in the sun and wears away, anyway. You might be able to go a little lighter with a fabric that uses a DWR but I would prefer to go with a durable waterproof coating and not have to retreat the pack material with DWR at a later date. Coat it and be done with it.
Yeah we agree, not really needed for bikepacking…
It’s good to know they are switching to safer chemicals (safe up to a point). DWR coatings from my experience and readings are not reliable once they get a little dirty. Like Teflon pans that stop being non-stick, the pores clog and water sticks better over time. In addition to DWR coatings on the outside of the fabric, the laminate applied to the inside of many materials also break down over time from friction rubbing or peeling off. I find that the best way to protect gear from rain is to simply put sensitive items that cannot get wet into zipper plastic bags or a sealable container.
Thank you for considering our and especially our planet‘s health and for sharing this information with us.
Love and respect for taking the time & effort into putting the planet first, and for sharing this information with us.
This is great that you guys provide all of this background information and commentary on the application for bike bags. I really appreciated having access to this summary and you guys posting it.