I have a townhouse complex where every single unit in one section is experiencing water damage around the sliding doors on the second floor of the 3 story town homes. Each floor has a deck with a patio door, one directly above the other. The water is coming from the 3rd floor to the 2nd floor and ruining the hardwood floors. The way the units were built, the decks were put on before the siding, but they seem to be flashed correctly around the ledger board, but I haven't taken a patio door out yet. Has anyone had a problem with vinyl patio doors leaking.