Raincoat no longer waterproof? A textile scientist explains why – and how to fix it

You pull on your rain jacket, step out into the storm, and within half an hour your undershirt is soaked. The jacket you purchased as “waterproof” seems to have stopped working, and all the marketing claims feel a bit suspect.

In reality, the jacket probably hasn’t failed overnight: a mix of how it’s built, the exact level of water protection it offers, and years of sweat, skin oil and dirt have all played a part.

But there are a few simple ways you can care for your rain jacket to ensure you…

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