How To Re-Waterproof Rain Gear
If your rain gear looks like it's seen better days, and doesn't seem to keep you as dry as it used to, don't worry: there's a (surprisingly simple) fix. Wash it.
Lightweight, protective, and durable, waterproof/breathable fabrics (whether they're 2-layer, 2.5-layer, or 3-layer) have undoubtedly been a huge boon to anyone who wants to get outside and not have to worry about inclement weather and all of its discomforts and dangers. These fabrics all have a couple of weaknesses, however—not only will contaminants like smoke, sweat, dirt, sunscreen and body oils hamper their membranes' breathability, their DWR (durable water repellant) coatings can eventually wear off. When these things happen, it can make wearing your favorite rain jacket feel more like you're wearing a garbage bag—your sweat can't evaporate off of your body, and you'll feel just as wet as if you weren't wearing a rain jacket at all.
Luckily, washing your technical rain gear isn't a big deal (really, don't be scared to do it), and with a little preparation, you can get it back to being as waterproof as the day you bought it.
Ideally, to keep your rain gear working as it should, you'll want to wash it at least once a season, probably twice, depending on how often you use it. If you don't want to wash it on a schedule though, you can keep an eye out for these signs and wash accordingly:
Rain Gear Cries For Help
- If the face fabric of your rain gear is wetting out, it means that the DWR has worn off, or at least has become deactivated. A wet-out rain jacket is not only heavy and well, wet, but the face fabric being saturated with water also means no vapor transfer can happen via the waterproof/breathable membrane. You're going to feel clammy.
- If your rain gear is visibly dirty, you're going to need to wash it. Remember, the way waterproof/breathable fabric works depends on millions of microscopic pores being able to vent water vapor from your body. If minute contaminants like smoke and body oil can prevent them from working properly, you'd better believe that caked on dirt will too.
- If you have 2.5 layer rain gear (like the Marmot Precip), and you see the waterproof/breathable membrane peeling or flaking away, I'm sorry: it's too late. Body oils are what killed it, and regular cleaning could have saved it.
How to Wash your Rain Gear
After reading the care instructions on your rain jacket, pants, or both (so there aren't any surprises), zip up their zippers and put them in your (front or top-loading) washing machine. Now here's the big caveat: You must use a detergent that won't leave any residue, like Nikwax Tech Wash, because a traditional laundry detergent will most certainly clog up their waterproof/breathable membrane. Use the amount of detergent specified on the bottle, and run a gentle cycle with cold water. If your washing machine has a 'second rinse' option, use it: you'll want to make sure that no residue (even from a detergent like Tech Wash) gets left behind.
After your rain gear is washed and rinsed, it'll need to be totally dry to assess your next steps. Heat reactivates a sleepy DWR coating, so as long as your jacket or pants' care instructions don't explicitly say that they can't be put in the dryer, tumble dry them on low heat for 15-20 minutes and not any longer. If they're still wet, hang them up until they dry completely.
Reapplying a DWR coating
If, after you wash and dry your rain gear, the face fabric is still is wetting out, you'll need to reapply a DWR coating. Nikwax (among other brands) makes both spray-on and wash-in solutions. While using the wash-in method is the most convenient (and ensures an even coating), it's unsuitable for jackets that have wicking liners; you'll have to use a spray-on coating for 2-layer jackets. After you apply the DWR coating, activate it with another tumble dry on low heat (or dry your gear in the sun). Once it's all dry, you're finished!