Ledger board spacers are designed to provide an air space between the house wall and the ledger board to prevent rot. Multiple stainless steel washers can be used or a variety of engineered products designed specifically for this application. Deck ledger board spacers are easy to install and provide a larger bearing surface area than washers.
Begin by cutting the ledger board to length and laying out the joist locations. The next step is to temporarily attach the ledger board and drill your bolt holes in between the joist locations. After the bolt holes are drilled you can remove the ledger board and attach the spacers to the house side of the board with fasteners. Next you seal the bolt holes at the house wall with silicone caulk. The final step is to position the ledger board into place and secure it by bolting through the spacers.