Step 1
Loosen any siding that is in place along the wall above the ledger board, if necessary. Use the claw of the hammer to loosen nails, or the drill to reverse any screws holding the siding in place. Gently pry the siding element loose along the top of the ledger board across its entire length.
Step 2
Squeeze silicone adhesive onto the top edge of the ledger board along its length. Also apply silicone caulking to the vertical portion of the wall along the top of the ledger board down the entire length. Slide the Z-flashing into place so that it slides up under the siding and across the top of the ledger board in the bead of silicone, with its remaining vertical section hanging down over the face of the ledger board.
Step 3
Reattach the siding on top of the ledger board, locking the Z-flashing in place. Install your pergola sections as you would normally, attaching them to the ledger board and running across your area. For best results, wait until the silicone adhesive has dried before you install your pergolas.