Retaining Wall Installation

Retaining walls hold back soil.

Homeowners and gardeners around the world use retaining walls on their property. These walls are a staple of multilevel yards and gardens, when one level of soil sits above another. Retaining walls hold the higher soil back, creating a tiered effect. The walls have to be properly constructed to hold the weight of the soil back and prevent it from spilling. Tall retaining walls should be professionally engineered and constructed, but homeowners typically can build walls less than 3 feet tall themselves. Proper preparation and installation of the wall will add value and interest to your home and garden.

Things You'll Need

• Stakes
• Hammer
• String
• Shovel
• Ruler or tape measure
• Wall blocks
• Gravel
• Tamper
• Level
• Sand
• Mallet
• Broom or brush
• Circular saw
• Coping blocks
• Landscape adhesive

Instructions

1. Drive stakes into the ground with a hammer along the perimeter for your wall line. Tie string to the stakes to provide a guideline for construction.

2. Measure the width and height of the blocks you intend to use for your wall. Dig a trench for your wall that is 4 inches wider than your blocks. Excavate the trench 6 to 12 inches deep -- depending on the size of your blocks -- so that half of each block will be buried below the soil line.

3. Lay a thin base of gravel in the bottom of the trench. The actual depth of the gravel will vary at each point in your yard, since the soil will not be even, but in general, you will spread gravel 3 to 6 inches deep. Rake the gravel out.

4. Compact the gravel with a plate tamper. Lay a level on top of the gravel, all along the trench, to make sure the surface is even.

5. Lay your first layer of blocks in the trench, using the level to make sure each block is completely even with the previous block. Place small amounts of sand under blocks if needed to keep the blocks level with each other. Pound the blocks with the mallet to set them in the sand and gravel.

6. Sweep all debris and dust off of the first layer of blocks.

7. Cut a block in half with the circular saw. Start the second row of bricks with this half-brick, then continue laying full bricks. This will offset the rows so all the joints don't line up. Complete the row with the other half of the block you cut. Check the blocks with the level.

8. Continue adding offset layers of wall blocks until you reach the desired height. Add coping blocks to provide a flat finish to the wall, if desired. choose. Spread landscape adhesive on the back of each coping block, then set it in place on the top row of blocks.

Tips & Warnings

• If your property slopes along the line of your retaining wall, dig your trench so that half a block will be buried at both the highest and lowest points on the wall, for best support.

• If your blocks do not come presplit, use a 3-pound mallet and 4-inch chisel to break the blocks along the splitting line.

• Backfill behind the wall with excess gravel and soil to help water to drain and prevent water damage to the wall.

• Find the supplies for your retaining wall at hardware and home improvement stores, as well as stone manufacturers.

• Keep your retaining wall less than 3 feet high. The higher you build the wall, the higher the chance of the wall cracking or falling.

• Take proper precautions when working with heavy tools and sharp edges. Wear proper safety equipment.

• Never lift heavy blocks without help if you are unsure about your physical condition.

References

• Ask the Builder: Retaining Walls
• Cap Brick Building Products: Wall Installation