How to Wash a Waterproof Jacket (Without Ruining It)

Your waterproof jacket has started letting the wet through, and the obvious thought is that it has worn out.

Usually it has not. The most common reason a waterproof jacket stops working is that it is dirty. Wash it properly with a technical wash, dry it with a bit of gentle heat, and most jackets come back. Reproofing is a separate job that far fewer jackets actually need.

The thing to avoid is the one most people reach for. Biological detergent and fabric conditioner will both damage a waterproof, and once that is done you cannot wash it back out.

So here is the whole process: what to use, how to run the machine, how to dry it, and how to tell whether yours needs reproofing at all.

Can you wash a waterproof jacket?

Yes, and you should. Washing a waterproof is not a risk you are taking with it, it is basic maintenance, and skipping it is what shortens the jacket’s life.

Here is why. The outside of your jacket has a water-repellent finish on it, which is what makes rain bead up and roll off. Body oils, sweat, suncream, campfire smoke and general grime all sit on top of that finish and flatten it.

When that happens the face fabric soaks up water instead of shedding it. That is called wetting out, and it feels exactly like a leak. The jacket goes heavy, the fabric sticks to your sleeves, and you get cold and clammy.

The membrane underneath is often still perfectly intact. It is just sitting under a wet blanket and cannot breathe. So the fix is a wash, not a new jacket.

How often? There is no schedule. Wash it when it looks dirty, or when water stops beading on the shoulders and sleeves, which are the areas that get the most wear and the most rucksack strap rub.

What should you wash a waterproof jacket with?

This is the part that ruins jackets, so it is worth getting right.

A technical wash such as Nikwax Tech Wash is the sensible default, and a bottle lasts a long time because you only wash one or two garments at a time.

If you are not buying one, non-biological liquid is the least-bad alternative. Run the garment through a second rinse afterwards to get the residue out.

The care label beats all of this. The manufacturer knows what their own fabric will tolerate. Read it before the first wash and follow it wherever it disagrees with general advice, including this article.

How do you wash a waterproof jacket in the washing machine?

Machine washing is fine and is what most manufacturers recommend. The detail that matters is preparation.

1. Empty the detergent drawer and run a rinse cycle if the machine has had ordinary detergent or conditioner in it. Residue in the drum is enough to undo the job.
2. Empty the pockets, do up the zips, including pit zips and pocket zips, and close any Velcro. Open Velcro will chew the face fabric of whatever it is next to.
3. Loosen the hood and hem drawcords so water can get everywhere.
4. Put in one or two garments, no more. They need room to move for the wash to reach the fabric.
5. Add the technical wash at the dose on the bottle, into the drum or the drawer as the instructions say.
6. Run a gentle cycle at a low temperature, usually around 30 degrees, and take the temperature from the care label rather than from habit.
7. Add a second rinse if you used anything other than a technical wash.

Do not dry clean a technical waterproof unless the label specifically says you can. The solvents strip the repellent finish.

Never Feel Lost Again: The Free UK Navigation & Safety Pack

Stop relying solely on a fragile phone battery. Download the exact tools a professional outdoor instructor uses to stay safe in the British hills.

Enter your email below to get instant access to:

• NEW: The Hike Planning & Safety Checklist: A comprehensive pre-walk checklist to ensure you never leave a critical item behind or rely purely on a smartphone.
• The Emergency Protocol Guide: A highly structured, zero panic system detailing exactly what to do if lost on Dartmoor/Scottish hills, including when and how to call Mountain Rescue.
• The OS Map & Navigation Cheat Sheet: A quick reference guide to decoding complex map symbols and plotting grid references when your mind goes blank.
• The Route Card Template: The exact, logic-driven framework I use to plan foolproof expeditions and identify safe escape routes before leaving the house.
• The Timing Crib Card: Never misjudge daylight again. Master the mathematics of measuring pacing distance and timings for steep ground.

Email Address*

How do you dry a waterproof jacket?

This is the step people skip, and it is the one that does most of the work.

Gentle heat reactivates the water-repellent finish that is already on the fabric. A jacket that beads badly before drying will often bead properly afterwards, with nothing added to it at all.

• Tumble dry on a low or cool setting for twenty minutes or so, if the care label allows it. Most technical waterproofs are fine with this and many manufacturers ask for it.
• Or use a cool iron, with the jacket dry, a cloth or tea towel between the iron and the fabric, and no steam.
• Or hang it somewhere warm, like an airing cupboard. Slower and less effective, but it is better than nothing.

Do not put it on a radiator, and do not leave it in direct sun for hours. Concentrated heat can delaminate the membrane or melt the face fabric, and that damage is permanent.

When does a waterproof jacket need reproofing?

Less often than the internet suggests. Reproof only when a clean, dry jacket still soaks up water.

The test that tells you

Splash some water on a clean, dry sleeve and watch it.

• It beads and runs off. The finish is fine. Do nothing.
• It sits flat, or leaves a dark patch that soaks in. That is wetting out, and now it is worth reproofing.

Test the shoulders and forearms as well as the body. Those wear first, so they will tell you before the rest of the jacket does.

How to reproof

Reproofers come in two kinds and the choice is straightforward.

• Wash-in, such as Nikwax TX.Direct, goes in the machine like a detergent. Easiest option, and it treats the whole garment including the lining.
• Spray-on is applied to the outside of a damp garment. More effort, but it treats only the outer face, which is the right choice for a jacket with a separate breathable lining you do not want coated.

Either way, the garment needs to be clean first. Proofing a dirty jacket seals the dirt in.

Dry it with gentle heat afterwards, the same as above, because most reproofers need heat to cure properly.

Is washing waterproof trousers any different?

No. Waterproof trousers, overtrousers and salopettes all take exactly the same process: technical wash, gentle cycle, gentle heat to dry, reproof only if the water test says so.

Two small differences worth knowing. Trousers usually get filthier than jackets, because they take the mud, so they need washing more often. And the seat and knees wear their repellent finish off first, so test those rather than the shins.

Do up the ankle zips before washing, the same as you would the jacket zips.

What should you never do to a waterproof jacket?

• Biological detergent. The single most common way people wreck a waterproof.
• Fabric conditioner. Its whole purpose works against yours.
• Bleach or stain remover. Both attack the coating.
• Dry cleaning, unless the label explicitly allows it.
• Drying on a radiator or a hot rail. Delamination is not repairable.
• Storing it damp, stuffed in the bottom of a rucksack. That is how the inside coating on cheaper jackets starts to break down and go sticky.
• Ignoring it for years and then blaming the jacket. A wash costs nothing.

What to do next

Here is your job for this week. Find your waterproof, splash some water on a clean dry sleeve, and see what it does. That thirty second test tells you whether you need a wash, a reproof, or nothing at all.

While you are looking at your kit, the layering system explains where the waterproof actually sits in what you wear, and the hill walking kit list covers the rest of the bag. Boots need the same kind of attention, and cleaning and waterproofing walking boots goes through that.

Free course: kit that works is only half of it. The free Digital Safety Net course covers the planning side, so you know the weather is coming before you find out whether your jacket still works.

Any questions, ask below.