When we get heavy driving rain, water comes in over the foundation wall, around the window casement (on both sides). I have vinyl siding and 'Crestline' windows that crank open sideways. I have purchased caulk and expanding ins. foam, but I need to know where to put the stuff. It's hard to tell where the water's coming in, as it looks like it's dripping down the behind the siding on either side of the window. Any suggestions? Also, can I put plastic right up against the window (over the casing) on the inside? THanks!