How to Repair a Collapsing Brick Landscape Wall

Brace the retaining wall on either side of the collapsing area. Place scaffolding planks up against the wall, arranged vertically, and use heavy timbers to hold them in place. Use a shovel to dig the bottoms of the bracing timbers into the ground, or strap them to lengths of rebar hammered into the ground.

Remove the burden of retained dirt from behind the collapsing area. Shovel it out and use a wheelbarrow to remove the dirt from the immediate work area so its weight is not able to exert an indirect pressure on the wall. Dig down until past both sides of the collapsing area and below the bottom of the collapsing area.

Remove all the bricks that make up the collapsing area. Typically landscaping walls are laid dry, meaning they are constructed without cement. This is almost invariably the case if they are made using concrete block or decorative stone block. Starting at the top center, lift the bricks away and stack them neatly to the side, continuing until the entire collapsing area has been removed. Ensure the stack is stable by making it low and wide, not tall and teetering.

If the bricks were laid wet -- using a bonding agent, usually concrete but occasionally silicone sealant -- it might be necessary to use a hammer and cold chisel to release them, even if the collapse has bellied out conspicuously. Follow the directions above, also tapping or scraping away the old bonding before adding each brick the stack. Alternatively, count the bricks you remove and buy an equal number of replacements.

Check the footing below the collapsed area if it extended below ground level. If the footing shows signs of collapse, has moved or is canted over at an angle, it must be replaced before rebuilding the brick wall.

Use a sledge hammer to drive long lengths of rebar into the ground through the wall line. If using hollow blocks, drive the rebar through the holes in the blocks and leave enough above ground to pass through at least the lowest two course. If using solid bricks, ignore this step.

Rebuild the wall using the original or replacement bricks. Follow the line of the courses that make up the braced sections on either side so the repair will not be noticeable. Lay the bricks dry if that was the original style, or copy the use of a bonding agent.

Reinstate the soil behind the repaired section of wall, but do not stomp or tamp the soil down firmly. If a depression forms after a few weeks, top off the area but again leave the soil as loose as possible.