Projects & Inspiration

What are the components of a wood fence?

October 4, 2018

Posted by Ashley VanderWall

Most residential privacy or spaced picket fences are made up of three main components: Posts, Backer Rails and Pickets.


Posts are the backbone of a wood fence. They sit vertically and are set into the ground with concrete. Properly set posts ensure a stable fence.

Wood fence posts are typically 4x4 (3.5” x 3.5” actual). The post height will vary depending on the height of the fence. (Keep in mind, the total post height is the fence height plus the amount of post that needs to be buried in the ground.)

Backer Rails

Backer rails, sometimes called fence rails or fence stringers, run horizontally from post to post. They connect to the posts with fasteners and are the fence components to which the pickets are attached. Depending on the fence height and style, there may be two or three backer rails running between each set of posts.

Backer rails are typically made with 2x lumber (1-1/2” thick). Because the backer rails span from post to post, the length depends on how far apart the posts are spaced. Most post spacing is 6’ or 8’.


Pickets, also called slats or boards, attach to the backer rails with nails or screws. They make up the body of the fence and are therefore the most visible component of the fence project. Pickets are available in multiple top styles such as dog ear, flat top and french gothic.

Pickets come in a variety of thicknesses, but the most common is 5/8” thick. Full 1” thick pickets are considered premium, while ½” thick is a more economical choice. Widths are typically 3-1/2” or 5-1/2” and height is typically 42” or 72”. Picket sizes are often labeled in nominal dimensions (ex. 1x4 may actually be 5/8” x 3-1/2") so it’s important to double-check the actual measurements when purchasing them.

Parts of a Wood Fence

A note on prebuilt fence panels

You can purchase backer rails and pickets separately, or may opt for a prebuilt (or preassembled) fence panel. With a prebuilt panel, the pickets are already attached to the backer rails. This saves time and energy during installation, but you may sacrifice some flexibility.

Add-On Fence Components

In addition to posts, backer rails and pickets, there are optional components that add function or style to your fence.

  • Post Toppers - Post finials and post caps are separate pieces that attach to the top of your post. They are a simple, DIY-friendly way to add style to your fence project.
  • Gates - Gates add a secure, convenient access to your fenced-in yard. You can build your own custom gate or purchase a prebuilt one to complement your fence.
  • Kick board - A kick board is a 2x6 or 2x8 piece of wood that runs along the base of your fence for a finished look and added protection.
  • Cap board - A cap board is also a 2x6 or 2x8 piece of wood that runs flat along the top of your posts and pickets. Before installing a cap board, it’s important that your posts and pickets are cut to the same height.
  • Trim board - Trim board are added to fence panels to create a finished look around the face of the fence.


Learn even more about wood fence by hopping over to our Wood Fence Projects Home.