One of the biggest issues that I come across when inspecting decks and porches is the lack of or improperly installed ledger board flashing. The ledger board attaches to the house rim joist and is what holds the deck to the house. So basically, this board is carrying half of the weight of the deck or porch. The ledger board should be attached to the home with either lag bolts or structural screws and these fasteners are typically staggered as to not split the ledger board.