I have a winter coat which I wear everyday, it's not a waterproof or softshell material but a polyester fabric. It was showerproof but I had to wash it, I did so in the machine and used non bio detergent as I thought this might be okay as it was non bio. But it washed the coating off the coat and it just started soaking up water whenever it rained. I was told I had 3 options:
1. Hand wash the coat in soap flakes to get rid of the detergent residue and then use a wash in or spray product to re-proof it.
2. Wash the coat in the machine with a special product and then use a spray or wash in product.
3. Use this product which would do both.
I was a bit sceptical as I couldn't understand how something could clean stuff out of a fabric and then waterproof it at the same time. But it works, really well, my coat now seems more water repellant than it was originally. Can also get a good few uses out of the bottle (contains 300ml and recommended use is 60ml per 2 kg).