How to Install Ledger Board for a Patio Cover

Installing a ledger board ensures the structural support of your patio cover. A ledger is a pressure-treated board that attaches to an existing wall to anchor a new construction or attachment and support the weight load. With basic carpentry skills, you can attach the ledger board to your home in a few hours. It's helpful to have a partner hold the board level while you attach it.

There's nothing like a patio cover on a sweltering day.

Refer to your municipal office to check the building codes for patio covers.

Use the pry bar to remove the siding from the exterior of the wall where the ledger will go and 1 foot above. Use the utility knife to cut the self-adhering waterproof membrane to fit over the exposed sheathing to protect it from the elements. Apply the membrane to the wall firmly with your hands.

Place the ledger against the building and snap a chalk line across the top. It's helpful to have an assistant to keep the ledger level.

Cut a wood spacer from pressure-treated wood for every 2 feet of length along the ledger. Use the circular saw to cut the spacers 2 inches wide and 1 1/2 inches thick. Line up the top of one spacer at a time with the chalk line and hammer 6d nails through the spacer, membrane and sheathing into studs or joists.

Hold the ledger across the spacers, aligned with the chalk line. Nail it on the spacers, sheathing and membrane with 16d nails.

Use the drill to make a 3/8-inch pilot hole through the ledger and into the home's rim joist. Place a lag screw and washer into the hole and tighten with the socket wrench by turning clockwise.

Cut equal strips of waterproof self-adhering membrane and metal flashing the length of the ledger and 6 inches wide. Cut the metal flashing with tin snips.

Fold the membrane in half down the length, forming a right angle. Set it in the house-to-ledger joint. Half the membrane will cover the top of the spacers and the ledger, and the other half runs along the wall.

Fold the metal flashing in half and place it over the membrane.

Hammer roofing nails through the top of the metal flashing every 8 inches.

Things You Will Need

  • Pry bar
  • Self-adhering waterproof membrane
  • Utility knife
  • Chalk line
  • Pressure-treated board
  • Circular saw
  • Hammer
  • 6d nails
  • 16d nails
  • Drill
  • Lag screw
  • Washers
  • Socket wrench
  • Metal flashing
  • Tin snips
  • Roofing nails


  • Because two nails will be going into each wood spacer, dip them in water before nailing so they don't split apart.


  • Wear protective eyewear when using power tools.

About the Author

Aurora LaJambre is a writer and editor living in Brooklyn, N.Y. For over five years she's covered topics in culture, lifestyle, travel, DIY design and green living for print and online media. Her publication credits include "WOW Women on Writing," "Six States" and Catalogs.com. She graduated from New York University in 2003 with a Bachelor of Fine Arts in creative writing.

Photo Credits

  • Digital Vision./Digital Vision/Getty Images