Draw an outline using a pencil and carpenter's level showing where the deck will fit against the house. Include the thickness of the outside joists and all decorative facing boards that will be installed.
Cut out the siding along the outline you drew in Step 1 using a circular saw. Where the circular saw blade does not reach, use a chisel to finish the cutout.
Measure and cut the ledger board from pressure-treated lumber using a tape measure and circular saw. The ledger is shorter than the overall length of the cutout in the siding.
Cut galvanized flashing to the length of the cutout in the siding of your home using metal snips. Slide the galvanized flashing up under the siding.
Hold the ledger in the cutout underneath the flashing, centering it with your hands. Secure the ledger in place using galvanized nails and a hammer.
Apply silicone caulking to the crack between the siding and the flashing using a caulking gun.
Drill pilot holes, spacing them every 2 feet, through the ledger and sheathing and into the header joists using a drill and 1-inch spade bit.
Attach the ledger to the house using lag screws, washers and a ratchet wrench.
Seal the lag screw heads with silicone caulking and a caulking gun. Seal the crack between the wall and the sides and bottom of the ledger with silicone caulking and a caulking gun.