How to Put a Fence on Top of a Retaining Wall

Karen Carter

Retaining walls are built to hold soil back usually at the bottom of a slope. When kids or pets need to be held back on the slope, then a fence is needed on top of the retaining wall. Depending on the strength of the retaining wall, the fence may have to be lightweight. Properly built retaining walls can hold heavy-duty fences. The fence posts will have to go behind the retaining wall instead of on top of the wall.

Lattice work builds a quick, sturdy fence.

Step 1

Dig the post holes for the fence in the soil behind the retaining wall with a post hole digger. Keep the holes straight up and down. Place a post hole every 6 feet along the top of the retaining wall. Dig down 26 inches in depth.

Step 2

Tamp the soil down in the bottom of the hole with the end of a wooden board to compact the soil. Dump a couple of shovels full of gravel in the bottom of the hole and tamp it down as well.

Step 3

Place a 4-inch-by-4-inch-by-6-foot wooden post in the hole. Mix together equal parts of soil and gravel. Use a carpenter’s level to keep the fence post straight.

Step 4

Fill the hole with the gravel mixture. Tamp the mixture down with the end of a board. Keep adding soil as the mixture is compacted until the hole is full. Install the rest of the fence posts.

Step 5

Measure 2 inches from the ground with a tape measure and mark this measurement on each fence post. Place a 1-inch-by-4-inch-by 6-foot board against the post and line the bottom of the board up with the 2-inch mark. With the wider side of the board against the post, secure the board in place with screws and an electric screwdriver. Do this with the rest of the bottom rails.

Step 6

Screw in more 1-inch-by-4-inch-by-6-foot boards into the top of the fence posts. Place the wider side of the boards against the posts lining up the top edge of the board with the top edge of the fence posts. Cut lattice work pieces with a saw to fit the framework of the fence. Staple the lattice work to the frame with an electric stapler.