The easiest way to waterproof a down jacket (or other down-insulated gear) is with a special wash or spray that's developed specifically for waterproofing technical fabrics and down-insulated gear. Nikwax and Granger's offer dependable waterproofing options that add or restore water repellency to the technical fabric of down jackets, vests and sleeping bags. You have two waterproofing options -- use a spray-on or an in-wash treatment. I'll walk you through both processes right here. In these instructions, I'll be referencing a down jacket, but keep in mind that you'll follow the same directions for other high-performance, down-insulated gear, like vests and sleeping bags.
How to waterproof a down jacket with a spray-on treatment:
1. Obtain a spray-on treatment like Granger's Xtreme Repel or Granger's Performance Repel. Make sure it is compatible with your jacket's fabric. Both of these treatments maintain that they are appropriate "for all technical fabrics," so they're a safe choice for most down-insulated outerwear.
2. Clean your down jacket. Before adding a waterproofing treatment, make sure it is clean and still damp. Don't know how to wash a down jacket? Learn how in our How to Wash a Down Jacket step-by-step guide.
3. Lay your damp down jacket flat and spray it evenly with the treatment from about 6 inches away.
4. Dry your jacket. Put your down jacket into the dryer to activate the waterproof treatment and thoroughly dry the down insulation. Don't forget to add some tennis balls or dryer balls to maintain loft.
How to waterproof a down jacket with a wash-in treatment:
1. Get a wash-in treatment like Nikwax Down Proof. The best thing about a wash-in water-repellent down garment treatment is that it not only adds water-repellency to the exterior of the jacket, but the lining and down insulation, as well.
2. Make sure your down jacket is clean before using the waterproof wash-in. If your jacket is dirty, clean it by following the directions in our How to Wash a Down Jacket post.
3. Clean residue out of the detergent tray and washer of your front-loading washing machine. This will ensure that your down gear doesn't get residual spots or discoloration during the waterproofing process.
4. Wash your jacket in the waterproof treatment. Measure and pour the appropriate amount of the wash-in waterproofing treatment into the detergent tray of a front-loading washing machine and wash your down jacket, vest or sleeping bag in warm water.
5. Dry your jacket in the dryer with a few clean tennis balls or dryer balls. The balls encourage the down insulation to maintain loft as it dries.