Since my water proof coat proved it isn't waterproof any longer after today's downpour....
What brand of waterproofing stuff do you lot use?
I use Nikwax spray on, don't rate it very highly though, may try something else when i've finished my very large bottle of it.
I just picked up some Granger's 2-in-1 this afternoon. I'll report back after I next get rained on...
Before shelling out on Nixwax, or Grainger's, you could try re-activating the proofing, by tumble drying on a low setting, or ironing at a low-ish temp, worked for me with a Endura Venturi II. (which uses a ptfe based membrane.)
tbh I've tried nikwax and grangers and neither seem to work very well.. the wash in is better than the spray on stuff.
If your waterproof jacket is a laminate (gore/event etc) and is genuinely leaking, then it's time to say goodbye to it as the membrane has degraded to some extent and no amount of spray or wash-in will fix the problem.
If on the other hand, you have been wearing your jacket in warmish, humid conditions, the chances are you got wet from a mixture of stuff coming in through the holes (neck/wrist) and your own juices from perspiration. Reproofing with a spray or wash-in (more accurately - replacing the water [b] repellent [/b]finish) will help water bead off the jacket and should help with the apparent breathability of the jacket (i.e. more of your sweat gets out)
I use grangers wash-in on my goretex jacket and trouser and found it lasted longer than Nikwax. The new stuff doesn't need heat treating either, which is handy. I use the spray on stuff on my paramo too and haven't found any problems.