Anatomy of the Wood Lattice Patio Cover

wood patio covers in Simi Valley Not everyone is a professional patio cover contractor. But when shopping for a new patio cover, it’s helpful to know what the various parts are and what purpose they serve. For those of us who have never really paid attention to the various components which make up a lattice patio cover, this page will hopefully bring you up to speed.

Components which make up a Simi Valley Wood Patio Cover

  • Footings
  • Beams
  • Rafters
  • Shade bars
  • Ledgers
  • Posts
  • Hardware


First of all, it’s the footings for the Wood Patio Cover that are the structural component and supports the weight of the entire patio cover system. For the most part, the footings can be as small as 12″ square or as large as 36″ square and even sometimes larger.

However, most of the time, the footings range from 12″-24″ in width and 18-24″ in depth. Footings are dug into the ground exactly where the posts are placed and filled with concrete. Rebar, which is a steel rod is not typically placed into these holes prior to filling them with concrete but can be. Of course, rebar is the material which more or less ties everything together structurally.

Wood Lattice Patio Cover Beam

Beams or girders are the main supporting members located at the front of the patio cover. Thus making it the most important piece of the Wood Lattice Patio Cover system. Wood beams support the rafters as well as the lattice bars.

Additionally, this structural component is sized specifically for each installation. Furthermore, the dimensions of the beam are determined by the length of the rafters as well as the width of the structure as a whole. Beam materials are typically constructed of Douglas Fir but can be a special structural system also known as a Glue Lam beam, made from individual wood pieces. Although wood is the most common material used, steel or aluminum are also options.

Wood Lattice Patio Cover Rafters

Rafters can be found running perpendicular to the beam and shade bars. The rafters are the wood members that attach to the house and lay on top of the beam. The rafters are the component that supports the top members called the lattice or shade bars.

For the most part, the rafters are sized according to the lateral spacing as well as the length, combined. Many times, the rafters can be a 2x, 4x, 6x or 8x wood member and are typically a free-of-heart-center wood member.

Patio Cover Shade Bars

Essentially, the shade bars are the single most important component of the wood lattice Patio Cover. The reason being is that the lattice bars provide the necessary shade which I’m sure you will agree is the entire reason for a lattice shade bar patio cover in the first place.

The Ledger

A ledger is a piece of wood that attaches to the house. Its also the point at which the patio cover will make it’s attachment to the building, respectively. Depending on your jurisdiction, the local building authority will have their own idea as to the correct way the ledger must be attached to the building.

Many times, the ledger is attached with “lag” bolts. These lag bolts will typically run through the ledger and into the interior of the house and connect into the wood framing within the building. At the point at which the ledger makes contact with the house, the top of the ledger is sealed to reduce the potential for moisture intrusion.

Lattice Patio Cover Posts

Posts of a patio cover are the vertical components that transfer the load of the roof directly into the earth. They are more or less, a very important structural component. Without the post, the cover could not stand. Too small of a post and the cover will be weak and likely to fall.


When we as contractors say “hardware”, we are essentially referring to the steel pieces which make all of our connections. For example, the connection between the footing and the post, the beam and the post and the rafter to the ledger. All of these connections use to some degree, hardware. Hardware can be manufactured by many different companies but here in Southern California, Simpson is the leader in Simi Valley Wood Patio Cover hardware.