Can you make clothing that is no longer waterproof 100% water-resistant again by waterproofing it? Clothing that is no longer waterproof cannot be made 100% so again, even with waterproofing. Related articles How do I wash high-visibility clothing? What is important to remember when caring for high-visibility clothing? I haven't had confirmation of my parcel being dispatched yet How long does basic waterproofing last and how often should I waterproof? How often should I wash soft-shell jackets?