How to wash and reproof waterproof jackets and trousers

During dreary UK winters, clothing that keeps you dry and warm is vital. 

But buying a top-rated waterproof jacket and a decent pair of overtrousers is only half the battle – the other half is keeping them rainproof.

Over time, dirt, dust and sweat can build up and stop the durable water repellent (DWR) coating on most outdoor clothing garments from working properly. Washing them incorrectly can have the same effect.

It’s therefore essential to keep your waterproofs clean, but to do it in the right way.

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How do I wash a waterproof jacket or trousers in the washing machine?

1. Only wash your waterproof if it really needs it – excess washing can wear down its DWR coating.
2. Before washing, give it a good brush down to remove excess dirt with a soft-bristled brush or dry cloth. Then remove anything detachable, secure zips and fasten pockets, flaps and snap closures.
3. Bio laundry detergent is never suitable for washing waterproofs. You’ll likely need a specialist technical fabric cleaner – but check what the manufacturer recommends on the label or website. Unless your jacket needs to be reproofed, choose one that simply washes it. You don’t need to reproof it every time it’s washed (see more on reproofing below). Examples of specialist laundry detergents are Nikwax and Grangers.
4. If a specialist product isn’t necessary, you may need to use a non-bio or alkaline-free detergent, but it’s vital to follow the instructions. Enzymes in regular detergents (particularly bio) can damage waterproofs by clogging pores in the membrane, affecting not only waterproofing but also breathability. Even detergent residue in the washing machine drawer can affect waterproof clothing, so wipe the drawer clean before putting on your wash. You could also run an empty rinse cycle to ensure the machine is fully clear of detergent residue. 
5. Don’t use fabric softener. Like detergent, it can ruin the membrane and damage fibres and colour fastness. Some detergents contain softeners, so beware.
6. Check the label on your jacket for how hot to set your wash. While some gear can withstand a 40°C wash, most need 30°C and a gentle spin cycle. Some machines have a specific waterproof setting, but you should still check the temperature, as it may not align with the manufacturer’s waterproof washing instructions, which could void your warranty.
7. Don’t fill the machine drum with lots of other items. It’s better to wash your waterproof on its own or with one or two other pieces of waterproof clothing of a similar colour.
8. Check the manufacturer's instructions on whether you should hang your waterproofs up to dry or tumble dry them. Heat can reactivate DWR, but not all clothing is suitable for tumble drying.

Looking to invest in new waterproofs? Be sure to check out the best-rated jacket brands, as well as the overtrouser brands walkers love. 

We've also rounded-up the best walking boots and the best wellies to get outside whatever the weather.

How to reproof a waterproof jacket or overtrousers

You can reproof in one of two ways. You can use a specialist technical fabric cleaner with built-in proofing to add to your washing machine. These wash-in waterproofers will coat your clothing during the wash cycle and activate while air-drying or tumble-drying. But only do this if the label says it's suitable.

Alternatively, use a waterproofing spray after you've washed your clothing. Hang it up and try to get even coverage across the outside of the jacket, taking care to cover the seams.

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