Rebuild of Retaining Wall

2009 Project

After moving into my fathers home we started repairing things around the house. One of the projects is an old retain wall that has 2 large fig trees in front of it and a flower bed on the up hill side.

The old wall was built about 20+ years ago using landscaping timbers The wall stands approximately 2.5 feet tall.

The nice thing about replacing a wall is you do not have to move much dirt, except for over the years the buildup of dirt that generally happens from mulch, decaying leaves and washing of dirt from up hill.


After removing the old timbers I was able to clean up the foundation by leveling it as much as possible and then use paver sand to make a level smooth area for the first course of the wall. Unfortunately I did not take pictures of the sand and the first course. Lowe's, Home Depot and other web sites have some good information on how to get started.


A few things to keep in mind that are a must do:


  • The first course of blocks must be in the ground, not on the ground. This sets the base that will help keep the wall in place and keep it from moving and keeps water from running under it and eroding the foundation.
  • The dirt wall needs to be sloping back on some walls as the blocks have a locking lip that will move the wall back 1/2 inch every 4 inches in height. You have to take this into account when planning so you have adequate room for the back fill of the wall.
  • All the blocks of the first row need to be level in all directions and level with the block next to it.
  • Have rock or fill dirty ready to set the row by backfilling it before going to the next.


Tools I used:


  • 4 foot level
  • 8 inch level (leveling each block of 1st row)
  • Shovel, ax and other yard tools
  • 6 foot 1x4 or 2x4 (use to level sand), straight of course.
  • 3 pound hammer
  • Mason chisel


Once I had the first row down the rest went pretty easy. You have to cut the end block to using a masonry saw or hammer and chisel which is what I did. Each row is offset half a block so that all the block are locked together.


After each row is in place, pour your rock or fill dirt behind the row and pack it down. You only want to fill this backfill just over half way or you will have to clean and remove some of it so the lip of the next row will fit and the block will sit flush and not move. I used a broom to sweep off the row before I set the next set to make sure there was not dirt to cause problems, just made things go better.

With a wall that steps back like this wall the corner will expand in all directions. As a result you will have to adjust for the difference.


As seen here I used a filler block to fill in the gap.

You continue the process until the wall the the height you need or the maximum height.

I stepped the block down to follow with the slope of the yard

This wall is the maximum height that the manufacturer suggest. The local home repair stores web site suggest a wall of no more than 2 feet tall, the manufacturer suggest 3 feet. Neither specify if it's the complete wall or the part that is out of the ground.


I have hauled off the timbers that were removed and need to finish the flower bed. But I think it was a good move to change the timbers to stone as it should last a life time.