When I went backpacking last weekend, I experienced ideal conditions for developing hypothermia. I was hiking through heavy mist and light rain, which grew heavier as the day wore on. Temperatures were in the low 40’s F and the wind was blowing at about 20 miles an hour. After a few hours of this, I got soaked and cold. The durable water repellent (DWR) coating on my Gore-tex shell had stopped shedding rain.
Gore-tex clothing is made by sandwiching a Gore-tex layer between two moderately porous fabrics. A DWR coating is applied to the external layer to prevent it from absorbing water. The DWR penetrates the fibers and lowers the surface tension of the external fabric, causing water to bead up and roll off of it when it gets wet.
Over time, the DWR coating wears off from normal wear and tear. When this happens, rain will saturate the external layer and the garment will stop being breathable. Sweat will build up inside the jacket, soaking everything you are wearing underneath.
When the temperature outside is cool and your jacket wets out, you are likely to feel chilled, even if you’re carrying a backpack and generating a lot of heat. That’s exactly what happened to me. I was wearing a single layer under my coat which became soaked as the sweat built up on the inside of my jacket. This caused my entire layering system to break down because there wasn’t a dry layer next to my skin to transport sweat away from it. My body reacted by trying to evaporate the water in my jersey, burning more calories in the process, which left me feeling cold.
I was very aware of the hypothermia danger when all this was happening. My hands were cold because my liner gloves had become soaked and my back was cold underneath my pack. I decided that I would stop and camp if I started to shiver. I added a polarguard vest to my layering system to preserve my core heat and then ate a big snack with cookies, crystallized ginger, nuts, and a packet of Justin’s Nut Butter, washed down with a lot of water. That warmed me up pretty good and I made it to my destination a few hours later, still wet and cold, but out of danger.
After I got home from that trip, I applied Revivex, a water-based DWR treatment, to my Gore-tex Jacket to prevent another episode of wet out. This process is easy and has 3 simple steps:
- Wash your jacket to remove any dirt or salt build-up. Read the care instructions on your jacket before doing this. I have a big bottle of a very gentle detergent that I use to was performance clothing called Revivex Pro which doesn’t leave behind any soap residue and is scentless. Scentless Woolite is also quite gentle and will also work just fine. Spin dry.
- When the coat is still wet, apply the Revivex Spray-On solution, applying an extra amount to the shoulders, hood, and at the ends of the sleeves. The external material should be wet but not be dripping.
- Let the coat air dry. Then put it into a dryer by itself and dry it for 60 minutes on low to medium heat.
The entire process takes under 3 hours and works like a charm. Water just rolls of my Gore-tex jacket now. The Revivex really does the trick. A single bottle will treat several garments.
Disclosure: Philip Werner bought these products with his own funds.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.