How To Build A Wood Retaining Wall

What You'll Need
4x4 posts
2x6 lumber
Carriage bolts
Circular saw

A wood retaining wall can solve a lot of problems that homeowners face with rolling or hilly landscape. You can use them to fix erosion problems, transform sloped land into a usable space and even create a lovely terraced garden going up the hillside.

Wood retaining walls have many benefits:

  • They use lightweight materials.
  • Durable, rot-resistant
  • Unique, easy to build
  • Assemble most of it off site

Building a retaining wall of blocks, concrete or rock can be hard work. However, wood retaining walls can be constructed very easily with a few simple tools and some basic woodworking skills.

Position Retaining Wall

Once you know where you want the wall then you begin to dig out and begin clearing out the ground near the area. Use a trowel or some other small tool to chop away at the brush.

Cut Posts

Cut your 4x4 posts to the length of your wall and then add up to 18 inches for sinking into the ground. If you are going to put up a 6 ft. retaining wall, then you will need to cut the posts to 7 ft. and 6 inches.


Before you begin digging holes and putting in the framework for the wood retaining wall, dig a small trench in between the areas where the posts will go. This will be for water drainage. Fill the trench with gravel.

Dig Holes And Pour Cement

Once the posts are cut, then lay them aside, and dig the holes you need on each side of the retaining wall area. They should be 18 inches deep.

Set the posts inside each hole and then pour quick dry concrete into the hole to hold the posts straight. Use 2x4 braces to keep the 4x4's completely straight. Level out the concrete and allow to dry for at least a week before doing any more work to the posts.

Install Boards

After the posts have had time to cure, you can begin cutting the 2x6 boards to fit the span between the posts. If your retaining wall is 10 feet long, then you will have had three posts in the ground. One on each side and one in the middle. Cut the 2x6 pieces to 10 foot lengths.

If the span is longer than your boards, then you should cut your boards so that they land in the middle of a post.

Bolt the boards to the posts, using the carriage bolts and bolting them to the outside of the posts.

Backfill the Area

Take a shovel and carefully start to backfill the area until the soil is back to the level of the landscaping and the top of the wood retaining wall. Once it is to the top then pack it down.


Plant your garden and add a little garden bench to enjoy the hard work you put in and the new scenery you have created.