Bravada, The worst leak I've had (fortunately!) was a small area under a poorly sealed kitchen window. In southwest Florida, there is no such thing as a few days of dry weather. Our summer rains are daily. So I draped a waterproof cover over that window, removed it and use an electricians drier (heavy duty hair drier) and carefully dried the area for a few days. As the exposed area dried, I'd leave it for a while, return to find moisture had wicked up. So I dried again. After 3 days, I was good to go. I used 3M aerosol contact glue (77?) with a long tube attached, sprayed as deep as I could get, between each layer of the plywood and braced and clamped for 24 hrs in the sun. Butyl taped and reset the window. I let the excess butyl seep out for a day or two and with a plastic scraper, removed the excess, then applied white Lexel caulk for a finished seal.
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