How to maintain Durable Water Repellency

Durable Water Repellent (DWR) treatment enhances the performance of a garments outer fabric by encouraging water to bead up and roll off the surface. A DWR finish bonds to the textile fibres to make them water resistant and improves existing water repellency of fabric.
DWR diminish in performance due to a number of factors—dirt, body oils, abrasion and repeated launderings. Often they can be revived by a washing and a few minutes of tumbling in a clothes dryer set on low or medium heat. With heavily used garments, DWRs eventually need to be reapplied by a spray-on or wash-in product.

Maintaining DWR

Wash the garment with an additive-free detergent or soap.  You can use regular laundry detergent, but you may have to give it an extra rinse or two to get rid of any residue. Do not use liquid detergents or delicate detergents as they contain fabric softeners that can impede the effectiveness of the DWR finish.