How to Build a Wood Picket Fence

Building a wood picket fence is easier than many people might think—it’s also incredibly rewarding. Follow this instruction guide for step-by-step instructions on installing your own wood picket fence. 

Objective:  By mastering this lesson, you will be able to build the most popular wood fencing that is both pleasing to the eye and functional.

Necessary equipment:  Nail guns, nail gun oil, compressor, air hose, hammer, pry bar, tape measure, string line, 12’ piece of plastic conduit, torpedo level, circular saw, six penny picket nails, sixteen penny rail nails, and loose six penny nails.

Key Questions:

  1. How to install the rails
  2. How to install the pickets
  3. How to build a picket fence

How to Install the Rails 

For each style of wood fence, the rails may be placed at different heights.  Once you verify the style of fence that you are building, you will be able to determine the wood fence rail spacing and location.  Ordinarily, the top rail is placed 7-8” from the top of the fence, the bottom rail is typically 7-8” from the grade and the middle rail is placed equidistant the top and bottom rails.  Do not place your rails any closer to either the top or bottom of the fence. 

Drawing of a 6' cedar solid privacy fence

Only once the concrete has hardened around the posts after you have installed them, you are ready to install the rails on your wood picket fence.  Though the steps stated below are generic enough to be applied to most wood fence styles, there are some individual differences that will be discussed later.

Diagram of rail positioning on post for a wood fence

  1. Lay your rails out three per fence section for six foot fencing and two per section for four foot fencing. 
  2. Mark your post with a crayon at top of the rail for each rail.
  3. With your posts set at 7’ 10” apart (center to center), start installing the fence rails at one end of the project, setting the first rail in line with the edge of the post.  The rails are installed to the outside of the fence toward the public or neighbor’s side.  This is important as it applies to some strict building codes that require the good side of the wood picket fence be facing out.
  4. As the rail extends to the next post, cut the rail at the center of the post.  Repeat this for all three rails.  Then, start with another rail butted firmly against the installed rail.  Again, cut the rail at the center of the next post.  In other words, the rails should always be joined at the center of the post. View the diagram above for a visual of this.  Use your circular saw to cut the rails.  Be careful not to cut too deep and into the post.
  5. Where the rail covers the post, install two sixteen penny nails at each end of the rail into the post.  To avoid splitting, make sure that you do not get too close to the end of the rail or next to a knot.
  6. Repeat this installation throughout the fence line.  When finished the rails should flow with the grade, as depicted below. 
Drawing demonstrating how wood fence rails should look after installation

How to Install the Pickets 

You will need to install the pickets on the neighbor’s or the public side of the fence, leaving the good side out. 

  1. Layout enough pickets at each bay based on your fence style, standing the pickets up against the fence.
  2. At each change in grade, temporarily nail one picket.  Do not worry about properly spacing these pickets.  Once you begin to install all the pickets, these temporary pickets will be removed and fit into the fence line. 
  3. Place a six penny nail half way into the top at the top of each temporary picket.
  4. Run a string line from temporary picket to temporary picket, wrapping the string around each nail as shown below.buildingapicketwoodfence-5.gif
  5. The string line represents the top of the fence and how it flows with the grade.  Evaluate the string line to determine if you can make any adjustments in the fence line to “make it flow better.”  You may raise a picket a couple inches above grade and you may slightly push a picket into the ground.  Too much variation will lead to a large gap at the bottom of the fence.
  6. After making your adjustments, start at one end of the fence line.  Place your first picket flush to the edge of the house or end of rails. 
  7. Each picket will receive two six penny nails at each rail.  Nail the picket to the rail with one nail at the top rail. 
  8. Before proceeding to add more nails, place your torpedo level along the side of the picket and level it.
  9. Refer to the section below on how to build a picket fence for your picket spacing. Return to this section and Step 10 to assure that your fence continues to flow.
  10. When encountering a temporary picket, move it so that it does not interfere with the spacing but keep the string line intact.
  11. Initially, install only two nails per picket.  At the end of the run, you can then go back and hit the remaining nails.  This is recommended in case you there are any mistakes or the fence gets out-of-plumb, which will be evident at the end of each run. buildingapicketwoodfence-6.gif
  12. buildingapicketwoodfence-7.gifWhen installing the nails, make sure that these are in the center of the rail and approximately one inch in from the side of the picket.  This is to avoid splitting the rail or picket.  Also, make sure that the nails are in a straight line. 
  13. The head of the nail should be slightly countersunk into the picket to assure that it does not come-out over time.
Under arch picket wood fence

How to Build a Picket Fence

A picket fence generally has a 2 ½” gap between the pickets. 

  1. Much like solid fence, install your first picket against the house or at the end of the rails. 
  2. Using a jig for spacing, space your next picket 2 ½” away. 
  3. You will have to level every picket on a picket fence.
  4. At the end of the line approximately four pickets from the end, measure from the fifth picket to the end of the fence. 
  5. Using that measurement, evenly space your last four pickets.