scampo said:Must be right, but my Helly Hansen never said to do anything except wash it and it lasted for very many years and saved me from some of the worst of Dartmoor's rain (which, I know is wussily wet compared to what you get north o'the border!).
I've never seen any other coats recommend NikWax either but what you say sounds fair enough.
Time for something definitive; I lifted this from the "North Face" website
"D. My shell jacket will not stay dry anymore. What can I do about it?
All of The North Face Outerwear shell fabrics are treated with a Durable Water Repellent finish (DWR). This finish helps the shell fabric resist wetting by causing the water to bead-up so it easily falls off before being absorbed into the fabric. Additionally, some of our performance fabrics have a waterproof back finish (such as Gore-Tex® fabrics and HydroSeal®) that prevents penetration of the water through the fabric. As a garment is worn and used over time, accumulation of soils from external sources as well as from your own body can lessen the performance of these finishes.
In order to revive the DWR, the product needs to be thoroughly cleaned with a powder detergent (do not use a liquid detergent) in a regular washing machine in warm water. Put the product through two rinse cycles to ensure that there is no detergent residue, then dry it in a regular clothes dryer on medium heat. When cleaning your Gore-Tex® jacket, attach all Velcro® closures and zip all zippers. Finally, the entire outside of the garment should be touched up with a warm iron on the steam setting.
This process should revive the DWR. For even better performance, treat your product with a coating of a DWR spray such as Tectron®. This maintenance program is only required when water stops beading up on the outer surface of the fabric."
I haven't used the spray ons such as Tectron as we always wash and then proof in the washing machine. So much more fun than reproofing a wax jacket whcih is what I have been doing while my wife watches "Holby City" (yuk!)
Andy