Is there a heavy-duty moisturizer you could put on your hands before you go to bed at night? I'm thinking along the lines of one of the ones that goes on more like ointment, not a light cream... that's likely to be the only time enough hours will pass that it will stay on long enough to be helpful; and if you have to wake up during the night and wash again, you can reapply when you go back to bed. Some soaps are also antibacterial but have moisturizers or aloe in them, so will be less harsh on your skin than others. I'd experiment with that. Even GermX comes in a version with aloe that might be worth a try.
Wearing rubber gloves when cleaning & washing dishes, etc may also help- it will help keep your hands dry and not exposed to the cleaning agents you use (which no doubt are irritating to already dried out skin.)
Thirty times a day sounds like a LOT to me, but my child with cf is older- she can blow her own nose, go to the bathroom on her own, cover her own cough and as a rule doesn't mouth random household surfaces... so it's different criteria to spread around the hand washing. <img src="i/expressions/face-icon-small-wink.gif" border="0">