Gear & Craft
Waterproofs stop working long before they look worn out
A jacket that wets out is not leaking. It is doing something more interesting, and you can usually fix it in an afternoon.
The options around waterproof shells are set out side by side below, with the conditions that genuinely favour one over the other.
The difference in one place
- Most "leaking" jackets are wetting out, not failing — the membrane is intact.
- Washing a shell restores performance; not washing it is what destroyed it.
- Reproofing is cheap, quick and reverses years of decline.
Wetting out is not leaking
A waterproof shell has two parts: a membrane that blocks liquid water, and a face fabric treated to make water bead and roll off. When the treatment wears off, the face fabric soaks through, and the wet layer sits against the membrane and stops it breathing. Moisture from inside then condenses on the membrane and runs down the inside of the jacket, which feels exactly like a leak and is not one.
The diagnostic is simple: if the outside of the fabric has gone dark and stopped beading, you are looking at wetting out.
Dirt is the main cause
Body oils, sunscreen, salt and general grime coat the face fabric and destroy the water-repellent treatment far faster than abrasion does. A shell worn for a season without washing will usually be wetting out badly, regardless of its price. This is why the manufacturer instruction most people ignore — wash it regularly — is the one that matters most.
On the ground, what is left in the machine matters as much as what you put in it, so an empty rinse cycle before washing a shell, and never letting fabric conditioner near one, avoids the commonest way people make the problem worse while trying to fix it.
Washing and reproofing actually works
Use a technical cleaner rather than detergent, because detergent residues attract water and make the problem worse. Most treatments are heat-activated: a tumble dry on low, or a warm iron with a cloth between, restores a surprising amount of performance. Where that is not enough, a wash-in or spray-on reproofer will return a five-year-old jacket to something close to new behaviour for the price of a coffee.
The choice between the two is not arbitrary, because a wash-in treats the inside of the garment as well as the face fabric and can dull breathability, while a spray-on treats only the outer surface, which is the surface that actually needs it on anything with a membrane.
Seams and zips fail before membranes do
Taped seams are the most common genuine failure point, and tape lifting is visible from the inside if you look. Water-resistant zips are exactly that — resistant — and are not intended to be watertight under sustained rain. Genuine membrane failure is rare and usually shows as a specific worn patch under a pack strap or a hip belt.
Lifting tape is repairable rather than terminal, since specialist repairers re-tape seams as routine work, and what accelerates the failure most is storing a shell damp or hot — which is what a car boot in summer amounts to.
Breathability is a rate, not a property
No membrane moves moisture faster than a person working hard produces it, which is why you are damp inside on a steep climb in any jacket. Pit zips and front zips move far more air than any membrane moves vapour, and using them aggressively is the practical answer. Rating figures published by manufacturers are measured under laboratory conditions that do not resemble a wet hillside.
Locally, the transfer also depends on a difference in humidity across the membrane, so in warm muggy rain there is barely any gradient to drive it and no jacket at any price breathes usefully.
How much of that applies depends on the terrain you are actually in.
What to check before you replace one
Wash it, dry it warm, and test with a hose or a shower before deciding it has failed. Inspect seam tape from the inside, particularly at the shoulders and the hem where it lifts first. Only then consider replacement, because a functioning shell that needs a wash is the most commonly discarded piece of outdoor kit there is.
Locally, when you test it, note where the water appears rather than simply that it did: entry at the shoulders points to seam tape, at the cuffs and hem to fit and adjustment, and an even clamminess across the back to wetting out rather than to any hole at all.
Side by side
| Consideration | What it means in practice |
|---|---|
| Most "leaking" jackets are wetting out, not failing | The membrane is intact. |
| Dirt is the main cause | Washing a shell restores performance; not washing it is what destroyed it. |
| Washing and reproofing actually works | Reproofing is cheap, quick and reverses years of decline. |
The takeaway
Wash it before you replace it. Most dead jackets are just dirty ones.
What holds up over a week outdoors is rarely what looks best at the trailhead.
Questions readers ask
How often should I wash a waterproof?
More often than feels right — roughly every ten to fifteen days of use, and always at the end of a season. Washing is what preserves the treatment, not what wears it out.
Are more expensive membranes actually more waterproof?
In practice they differ more in breathability, weight and durability than in whether they keep water out. Almost any current membrane will stop rain; the difference shows up over years of use.
