How To Build a Backyard Retaining Wall Yourself

If your home is built on a slight elevation from the rest of the street and you don’t know what to do with your lawn, a retaining wall can come in handy. Transforming a sloped patch of yard into something spectacular is just a great way to enhance your landscape, but it also gives you a solid project to get your hands dirty with over a weekend or two. So grab your gloves, and let’s get into it!

Materials Needed for Retaining Wall

1. Retaining Wall Blocks: Choose blocks with a lip on the back to help lock them together.
2. Type 2 Gravel: For the base layer and for drainage behind the wall.
3. Coarse Gravel: For additional drainage, especially behind the wall.
4. Topsoil: For covering the top and planting grass or other plants.
5. Landscape Fabric: To separate the gravel from the underlying soil and prevent weed growth.
6. Drain Pipe (optional): Necessary if you have a tall wall or poor drainage.
7. Masonry Adhesive: For securing capstones or top layer blocks.
8. Capstones (optional): For a finished look on top of the wall.

Tools and Equipment Needed

1. Shovel: For digging the trench and moving soil.
2. Pickaxe: Useful for breaking up hard soil or rocky ground.
3. Tamping Tool: For compacting the gravel and soil.
4. Level: Essential for ensuring blocks are laid evenly.
5. Garden Rake: For spreading gravel and soil.
6. Wheelbarrow: For transporting materials like blocks, gravel, and soil.
7. Rubber Mallet: For adjusting the blocks without damaging them.
8. String Line and Stakes: To keep your wall aligned and level.
9. Measuring Tape: For precise measurements of length and depth.
10. Safety Glasses and Gloves: Always important for protection.
11. Landscape Stakes and Hammer: For securing landscape fabric.
12. Caulking Gun: For applying masonry adhesive.
13. Chisel and Mini Sledgehammer: For cutting blocks if necessary.

How To Build a Retaining Wall

Step 1: Design and Plan Your Wall

First things first, you need a solid plan. If you’re aiming for a three-foot-high retaining wall like the one I’m about to describe, you’ll need to consider a few key elements. Your design will vary slightly depending on the height of your wall, but the basics remain the same.

Start with a strong foundation: a six-inch layer of packed type 2 gravel. This isn’t just any dirt—it’s what keeps your blocks in place and prevents your wall from collapsing. You want this layer to be as robust as possible.

For the blocks, I recommend using ones with a small lip on the back. They lock together nicely, are cost-effective, and you can find them at most hardware stores. Behind the blocks, plan for another six-inch layer of gravel for drainage—this is crucial for water runoff, especially during heavy rains.

If your wall is tall, consider installing a drain pipe at the base to help with extra water pressure. Always check with your block supplier for specific advice about drainage and block placement.

Cover the top with enough topsoil to grow grass or plants, making your wall not only functional but also a pretty feature in your garden. Remember, the area behind the wall will be packed with soil to ensure stability, and you’ll want to cover at least half of the bottom block with soil to make sure your wall stands firm.

Step 2: Excavate and Prepare the Base

Roll up your sleeves because it’s time to dig! For a wall with a good, solid base, you’ll need to dig a trench about nine inches deeper than your planned ground level. This part can be a bit of a workout, especially if you have rocky or hard soil.

Make sure your trench is level before filling it with gravel. I can’t stress enough how important a level base is to prevent your wall from leaning or buckling down the road. Once you’ve dug your trench, line it with landscape fabric to keep weeds at bay and prevent your gravel from mixing with the soil.

Step 3: Lay the Gravel Base

Layer your gravel in two-inch increments, compacting each layer before adding more. This step is crucial for creating a stable base. Keep the gravel slightly damp to help with the compacting process. You want to achieve a total thickness of about six inches of packed gravel.

Step 4: Start Laying Your Blocks

Begin laying your blocks at the lowest point of your wall. Place each block carefully, using a level to ensure each one sits perfectly flat. The lip on the back of each block should hook over the one beneath it, locking them together. As you lay the blocks, backfill the area behind them with gravel for drainage and tamp it down to prevent settling.

Step 5: Build Up Your Wall

Continue stacking the blocks, checking periodically with a level to ensure the wall remains even. As your wall grows, keep backfilling with gravel and compacting the soil behind it. This step is repetitive but gives you a rhythm as your wall begins to take shape.

Step 6: Top Off and Finishing Touches

Once your blocks are all in place, you can add the finishing touches. If you want a polished look, consider capping your wall with a row of flat stones or special cap blocks. These can be glued down with masonry adhesive to prevent shifting.

For added stability and to help with drainage, consider adding more gravel behind the wall, extending out several feet. Slope this gravel away from the wall to help direct water runoff.

Step 7: Clean Up and Landscape

With the structure complete, clean up any excess materials and tools. Now’s the fun part—landscaping! Plant some shrubs, flowers, or even a small tree near your wall to help integrate it into the rest of your garden. This not only beautifies your space but also helps to prevent soil erosion around your new structure.

Building a retaining wall is a fantastic weekend project that not only enhances the look of your yard but also adds functionality to your space. Whether you’re a seasoned DIYer or a casual hobbyist, the satisfaction of building something durable and beautiful is unmatched. So why not give it a shot? By following these steps, you’ll create a sturdy and stylish retaining wall that will last for years to come.