How to Repair a Brick Retaining Wall

Lead Image
  • 24-48 hours
  • Intermediate
  • 1,000-10,000
What You'll Need
Wire brush
Drill mixing attachment

The purpose of a brick retaining wall is to keep soil that is sloped and elevated from collapsing like a landslide. These walls are built to withstand a lot of pressure. Unlike a solid concrete wall or even a cinder block wall; a brick retaining wall typically needs more repair. The chief cause of a brick retaining wall requiring repair is due to crumbling and aged mortar. The mortar used to build a brick retaining wall is not a special kind of mortar so it can fail but it can also be repaired. The bricks themselves rarely fail but they can also be replaced. The article that follows will explain how this can be done.

Step 1 – Determine the Damage

Knowing the extent of the damage is very important to how you are going to go about fixing the brick retaining wall. You will want to look for missing mortar as well as cracked bricks. Check for chunks of missing brick as well. Loose mortar will also need to be removed as, in time, it will crumble and fall out of the wall.

Step 2 – Prepare the Wall

In order to repair the brick retaining wall you first need to remove the damage, you found in Step 1. The easiest way to do this is by using a wire brush. The bristles are stiff enough to remove any loose brick or mortar. Brush over the wall with it using medium pressure so that you brush away loose mortar and piece of brick. If some of the bricks are too damaged to be repaired you can remove them. Place the chisel along with the mortar and gently tap it with the mallet. Once enough mortar has been removed you can then remove the brick. Clean the leftover mortar from the bricks with the chisel until you have a clean surface.

Step 3 – Repairing Mortar

Repairing bad mortar is fairly easy as it is done the same way as applying fresh mortar. Mix mortar in a bucket according to the packages directions. Mix it with a drill that has a mixing attachment on it. Make sure the mortar is smooth and thick like oatmeal. Use the trowel and put a thick layer of mortar over the area to be repaired and then spread it out. Apply as much mortar as needed in order to refill the empty area.

Step 4 – Replacing Bricks

Replacing brick in a retaining wall is also fairly simple. The mortar is mixed the same way as stated in Step 3 and is then applied in a thick layer on the site. The brick is placed on top of the mortar and is seated using the mallet to gently tap it down. Apply more mortar to the top and to the sides as needed in order to fill and spaces. Use the trowel to smooth the mortar over it and more mortar in any areas that require it.