TAPED & SEALED SEAMS Jackets can be treated with a waterproof coating and have a waterproof membrane, but still not be fully waterproof. To make a jacket 100% waterproof, you need to add tape to the seams on the inside of the jacket. The tape is heat glued on top of the seams, which will stop water from seeping through the stitches. The process of adding taped seams is especially important if you wear your jacket in heavy, prolonged rain.
