I did not see any water issues other than the back door i replaced due to water problems, but that was a different problem. behind the hardiplank is osb board. I dont see any flashing around the windows, but they are new construction windows and I did not see any water problems around the one I removed. I also have not had any moisture problems in the home (other than the crappy windows I will be replacing). So if I have no moisture problems, it would not be beneficial to wrap now? Again thank you so much for the advice, Matt