Why your jacket “stopped working” and why it is almost certainly not broken

The story is always the same: the jacket was excellent for two seasons, and now it “drinks” water and turns heavy and cold. The first thought is a ruined membrane and a new jacket. The truth is almost always cheaper: only the DWR, the water-repellent finish on the outside, has worn off.

The membrane in a jacket is a thin film with microscopic pores, which let vapour out and keep droplets from getting in. It only works while the outer fabric is dry. DWR is what makes rain bead up and run off. Once the finish wears off, the fabric soaks through. The membrane underneath still holds, but the jacket goes wet, heavy and “clammy on the inside”.

DWR does not fail overnight. Dirt, sweat, pack straps and time wear it down. The first sign: rain no longer beads, it spreads into dark patches. That is the moment for care, not for a purchase.

There are two things you can do at home. First, wash the jacket, because a clean membrane breathes far better and a dirty one is clogged. Use a liquid detergent made for membranes, never fabric softener, which finishes the finish off for good. Second, renew the DWR with a spray or a wash-in product, and activate it with heat as the instructions say.

If you would rather not risk it: this is our most common job. We wash the jacket, renew the finish, set it with heat and check the seams. If the inspection shows the membrane really is at its end, which does happen after many years, we tell you and charge you nothing.

One rule to finish with: technical clothing usually dies of unwashed dirt and fabric softener, not of use. Wash it less often than ordinary clothes, but wash it properly.