When your leather jacket gets wet, it loses some of its essential oils, potentially leading to a dry, brittle texture and unsightly -- and usually permanent -- splotches and spots. Waterproofing leather isn't common, but it is a doable DIY project. While waterproof leather, which typically comes at a premium cost, features a hydrophilic wax injection or the application of a water-wicking surfactant, you can use off-the-shelf products to waterproof you leather jacket at home.
Choose a silicone polymer leather waterproofing spray if you have a napped leather jacket, made of a material such as suede or nubuck. This type of spray repels water by adding a slightly slick coating to the material.
Go with an acrylic copolymer spray for a more flexible treatment that penetrates the leather to create a microscopic net that is porous but water-resistant. Acrylic copolymer sprays typically do not alter the color of the garment. These sprays lend themselves to smooth, genuine leather materials.
Test your treatment on a small, inconspicuous part of your jacket before applying the treatment to the entire garment. Waterproofing your jacket may alter the color or texture of the leather.
Drape your clean and dry leather jacket on a clothes hanger so it hangs flat. Choose a well-ventilated area away from extreme heat or open flames. Hold the jacket about 6 to 8 inches from the nozzle of your silicone polymer or acrylic copolymer spray. Apply a light, even coat of the spray to the entire leather surface of the jacket. Gently stretch the jacket and hold it flat with one hand as you spray with the other to ensure an even application that doesn't miss any of the cracks, folds or crevices of the leather.
Allow the jacket to air dry completely before wearing.