Nothing is forever. Count the water resistance of your hardshell rain jacket among the things that wear out and disappear over time. That’s right, outdoor rain jackets can become water-logged long before the stitches give out or the zippers begin to jam. You don’t need to replace it, though. You can re-treat it as easily as misting a houseplant or doing the laundry.

You know these rain jackets and rain pants by the most popular brand names of their fabrics, such as Gore-Tex and eVent. These days nearly every outdoor clothing manufacturer is creating their own proprietary fabrics that function basically the same way. To achieve water resistance, a DWR (“durable water-repellent”) coating is applied to a semipermeable membrane that lets the jacket or pants ventilate body heat and perspiration. The coating means you shed raindrops like water off a duck’s back, at least while the garment is still relatively new.

But from abrasions such as pack straps against shoulders, repeated downpours, and at-home washing, the DWR coating wears off bit by bit until your rain clothes become more sponge than duck’s feather. Don’t toss that rain jacket or pair of rain pants into the trash. With a few bucks and a few minutes, you can make them almost as good as new.

Updated October 2023: We’ve got a new recommendation for the best way to apply DWR, phasing out our old favorite method of spraying it on.

Special offer for Gear readers: Get WIRED for just $5 ($25 off). This includes unlimited access to WIRED.com, full Gear coverage, and subscriber-only newsletters. Subscriptions help fund the work we do every day.

If you buy something using links in our stories, we may earn a commission. This helps support our journalism. Learn more.

How to Tell When Your Waterproofing Is Wearing Off

The big visual cue is that you’ll see dark, wet patches. Where water once beaded up and ran off, it now soaks into the fabric. That’s called “wetting out.”

Feel around on the inside of the fabric behind the dark patches. Does it feel wet? If it is (and you’re sure it’s not just sweat), it could be that water is soaking through and your jacket or pants need a new application of DWR.

A note about wetting out after heavy rain: Even new, hardshell jackets can wet out after prolonged, very heavy rain. So if you’re seeing dark, wet patches after a long time in a storm, it doesn’t necessarily mean you need a new coating of DWR. Do a little detective work to find out for sure. Once you take the clothing home and it has a chance to dry, squirt it with a spray bottle full of water to see if moisture beads up. If it wets out again, it’s time for more DWR.

Clean the Clothes First

Wash your garments before re-waterproofing them to remove body oils and old dirt. It’ll help the new DWR coating adhere better to the fabric. Outdoor retailers will try to sell you a detergent made specifically for technical outdoor clothing, such as Nikwax Tech Wash, but you can save your money and use a regular laundry detergent. I’ve been using regular, old Tide Free & Gentle detergent on my outdoor clothing for years, and it’s done as good a job. After washing, you’re ready to apply the DWR treatment. You’ve got two options here: wash-in or spray-on.

How to Apply Wash-In DWR

After years of relying on spray-on DWR, I’ve moved on to using wash-in DWR treatment—with a twist. From hiking through the rainforests of Hawaii to mountaineering in Alaska, I rely on my hardshell jackets and pants to keep me dry. Leaky rainwear in temperatures that cold can be dangerous, even fatal, so I’m very particular about making sure my hardshell gear is as water-resistant as can be.

Your best options for a wash-in DWR are Gear Aid ReviveX Wash-In, Grangers Repel Wash-In, and Nikwax TX.Direct Wash-In. The instructions tend to say you should wash them separately from your regular clothes in either a top or front-loading washing machine set to a warm water, gentle cycle, and dump the liquid into the washing machine.

I prefer to fill a bucket with lukewarm water, dump the detergent into it, stir it together, and then let the clothes soak in it overnight. Garments will often float to the top, so use something to weigh it down that won’t bleed color. I’ve usually got a spare bottle of Drano or Tide lying around, so I usually use that.

The next morning, toss the clothes into the washing machine or hand-wash them. Just keep your other clothes separate. Some DWR treatments instruct you to follow up by tossing the garments into a dryer set to a low-heat cycle to seal in the coating. Just check the instructions on the bottle of the stuff you’re using first.

Navigating a 12-hour day through an all-day whiteout in Alaska’s Denali National Park this May, my freshly re-waterproofed jacket shed ice crystal meltwater perfectly. Two months later on Mount Baker in Washington, the water resistance held up just as well. You can expect to get a season’s worth of use from one re-treatment. In the past, I’ve made the clarification that you can get your garment’s water resistance close to its original performance, but not exactly equal. After using the soak-and-wash method for this season, it seems that the water resistance on my Arc’Teryx jacket and pants are as good as they were when new.

How to Apply Spray-On DWR

For spray-on options, there’s Gear Aid ReviveX Spray, Grangers Performance Repel Plus Spray, and Nikwax TX.Direct Spray. 

Whichever you choose, take it outside to apply it—it’s not good to breathe this stuff in. Just hang your garment on a hanger outdoors, zip up the front and close the pockets, and spray the exterior of the jacket or pants.

One spray can is enough to re-waterproof one outfit—meaning a jacket and pair of pants. In my experience, there’s just barely enough though, so don’t waste it by spraying any particular spot on your garments for too long. If you have any left after you finish, apply it to areas that see lots of friction, such as shoulders, armpits, and the crotch/upper thigh area.

Like with wash-in DWR,  some DWR treatments require you to toss the treated garments in the dryer. Skipping this step means the jacket won’t be all that waterproof when you take it through a rainstorm. Once, I got distracted and forgot this step. It took just a few minutes for my jacket to soak through as if I’d never even sprayed the DWR on at all.

How Long It’ll Last

Reapplications of DWR don’t last as long as the factory-applied treatment. There’s no way around it. You’ll just have to get used to checking your rain gear before trips and reapplying DWR as needed. High-impact areas, such as shoulders and armpits, are exposed to more abrasion, and these areas tend to lose their waterproof coating sooner than others.

DWR treatments, for a long time, used long-chain perfluorocarbons (PFCs) that created toxic byproducts during manufacturing and disseminated into the environment as the product wore down. The DWR treatments we recommend—ReviveX, Grangers, and Nikwax—use fluorocarbon-free formulas. Though you may balk at the idea of introducing more synthetic chemicals to your gear, these treatments increase the lifespan of your clothes several times over, creating less waste over time.

The more you use the garment, the more quickly the DWR coating will wear off. But there’s no limit to how many times you can reapply DWR. As long as the clothing is in good shape, you can keep re-waterproofing it over and over for years to come and save yourself from having to replace a several-hundred-dollar rain outfit.