How to re-waterproof an old rain jacket
Feel the inside of the fabric behind the dark spots. Is it wet? If it does (and you’re sure it’s not just sweat), water may seep in and your jacket or pants may need a new application of DWR. .
Note regarding humidity after heavy rains: Even new hardshell jackets can get wet after prolonged very heavy rains. So if you see dark and wet spots after a long period of thunderstorm, it is not. necessarily means you need a new DWR coating. Do a little detective work to be sure. After you’ve brought the clothes home and they’ve been able to dry, spray them with a spray bottle filled with water to see if the moisture builds up. If it gets wet again, it’s time to apply more DWR.
Clean clothes first
Wash your clothes before waterproofing them to remove body oils and old grime. This will help the new DWR coating to adhere better to the fabric. Purchase a cleaning product specifically designed for technical outdoor clothing, such as Nikwax Tech Wash, although you can use a small amount of regular laundry detergent instead.
You will want to wash them separately from your usual non-outerwear clothes. Then you are ready to apply the DWR treatment. You have two options here: spray or rinse.
How to apply DWR spray
Whichever you choose, take it out to apply it – it’s not good to breathe that stuff. Simply hang your garment on a hanger on the outside, close the front zipper and pockets, then spray the outside of the jacket or pants.
An aerosol can is enough to re-waterproof an outfit, that is to say a jacket and pants. In my experience, there is barely enough of it, so don’t waste it by spraying one particular spot on your clothes for too long. If you have any left over after you’re done, apply it to areas that experience a lot of abrasion, such as shoulders, armpits, and crotch / upper thigh area.
How to apply the DWR Wash-In
Typically, you’ll want to use a DWR wash treatment in a top-load or front-load washing machine set on a gentle cycle with lukewarm water, but check the bottle of the product you’re using. Your best options are Gear Aid ReviveX Wash-In, Grangers Repel Wash-In, and Nikwax TX.Direct wash.
If you don’t have a washing machine handy, you can apply the product by hand with a sink or bucket of lukewarm water and gloves. Some DWR treatments require you to follow by tossing the clothes in a dryer set on a low heat cycle to seal the coating. Just check the instructions on the bottle of the products you use first.
How long will it last
DWR reapplications do not last as long as the factory treatment. There’s no getting around this – you’ll just have to get used to checking your rain gear before travel and reapplying the DWR if necessary. High impact areas, such as the shoulders and armpits, are more prone to abrasion, and these areas tend to lose their waterproof coating sooner than others.
DWR treatments have long used long-chain perfluorocarbons (PFCs) which created toxic byproducts during manufacturing and dispersed into the environment as the product wears out. Our recommended DWR treatments – ReviveX, Grangers and Nikwax – use fluorocarbon-free formulas. While you may be hesitant to introduce more synthetic chemicals into your gear, these treatments multiply the life of your clothes, creating less waste over time.
The more you use the garment, the faster the DWR coating will wear out. But there is no limit to the number of times you can reapply the DWR. As long as the clothes are in good condition, you can keep waterproofing them over and over again for years to come and save yourself the trouble of replacing a multi-hundred dollar rain suit.
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