DIY Retaining Wall: 7 Simple Steps for Your Backyard Makeover

I still remember the first time I decided to build a retaining wall in my backyard. The slope behind my house looked harmless—until the first heavy rain. Within hours, half the garden soil had slid down the path, and I was left with a muddy mess that looked nothing like the neat terrace I had imagined. That weekend, I picked up my shovel, watched a few tutorials, and started what turned out to be one of the most satisfying projects I’ve ever done.

If you’ve been staring at a slope that refuses to stay in place or dreaming of turning an uneven patch into a clean, usable space, a retaining wall might be exactly what you need. It’s not just about holding soil; it’s about reclaiming control over your landscape—adding shape, strength, and a touch of design all in one go.

Over the years, I’ve learned that building a retaining wall isn’t about brute force or complicated engineering. It’s about doing the right prep, understanding the soil under your feet, and following a few simple rules that keep everything standing season after season. In this guide, I’ll walk you through the seven easy steps to build your own retaining wall—without expensive tools, backbreaking mistakes, or guesswork.

Before we get into it, tell me—what’s your reason for wanting a retaining wall? Is it for function, beauty, or both?

Why Retaining Walls Matter — More Than Just Decoration

When I built my first retaining wall, I thought it was just about keeping soil in place. But once it was done, my backyard looked completely different — level, defined, and surprisingly peaceful. That’s when I realised: a retaining wall isn’t just a barrier, it’s a transformation. It turns a messy slope into a usable, structured part of your home.

A well-built retaining wall does much more than most people think:

• Prevents soil erosion and flooding: Rain naturally washes soil downhill, but a wall stabilises it and protects your yard from damage. As explained by experts at This Old House, compacting a proper base and building in drainage layers are the keys to preventing erosion long-term.
• Adds usable space: By flattening uneven ground, you can create patios, play areas, or even tiered gardens where water used to run wild.
• Boosts property value: Structured landscapes are a big plus for curb appeal — they make your home look cared for and thoughtfully designed.
• Blends with your home’s character: Whether you prefer modern stone blocks or rustic wood, a retaining wall can match any backyard style.

Once you understand how much stability and design a single wall can bring, you’ll see it less as a “construction project” and more as an investment in how your home feels and functions.

Know Your Terrain — Assess Before You Build

Before lifting a single block, take time to study the ground beneath your feet. Every yard has its own challenges — soil that holds water, slopes that shift, or drainage patterns that no one notices until the first big storm. I learned this the hard way; what looked like a harmless slope in my yard turned into a small landslide after one night of heavy rain.

Here’s how to assess your space before you start:

1. Check Your Slope Angle and Soil Type

• Examine the slope: Anything steeper than about 30 degrees needs more support or a tiered design.
• Do a simple soil squeeze test:
  • If the soil crumbles easily, it’s sandy — great drainage but weak structure.
  • If it sticks together, it’s clay — strong, but traps water behind walls.
  • A balanced, slightly gritty feel means loam — the ideal mix for retaining strength and drainage.

Knowing your soil helps you plan the base, backfill, and drainage correctly.

2. Identify Water Flow and Drainage Direction

Water is the silent test of your wall’s strength.

• Watch your yard after rainfall or do a hose test to trace how water moves.
• Look for puddles — they’re clues to where pressure builds up.
• Plan where the runoff will exit safely, usually through gravel backfill and a drainpipe.

A landscape designer once said something that stuck with me: “If you don’t respect the water, it’ll find a way to move your wall.” Trust me — figuring this part out before building can save you from rebuilding later.

Choose the Right Retaining Wall Type for Your Yard

When you first decide to build a retaining wall, it’s tempting to think, “Blocks are blocks—how different can they be?” I made that mistake once. By the next rainy season, my “simple” wall started to lean like it had a secret. The truth is, not all retaining walls are created equal. Choosing the right type for your slope and budget is the real foundation of the project.

Here’s how to decide what works best for your yard:

1. Gravity Walls — Simple and Perfect for Small Slopes

If your slope isn’t too steep and you’re building a wall under four feet, a gravity wall is your best friend.

• Relies purely on its own weight for stability.
• Ideal for DIYers using concrete blocks, stones, or bricks.
• Requires a solid, compacted base and good drainage.
  Think of it as the “keep it simple” approach—strong enough for most gardens without the need for complex engineering.

2. Cantilevered & Anchored Walls — For Steep or Large Projects

If your wall needs to hold back a lot of soil, especially on slopes or multi-level yards, cantilevered or anchored designs are the way to go.

• Cantilevered walls use a concrete base with a steel-reinforced stem to distribute pressure evenly.
• Anchored walls use cables or rods driven deep into the soil to lock the wall in place.
  These are typically built with professional help, but they last for decades when done right.

3. Modular Block vs Timber vs Stone — Cost & Design Comparison

When it comes to materials, think about both look and longevity. Each one has its own balance of cost, maintenance, and appearance.

As The Spruce explains, your material choice directly affects durability and cost—but also how seamlessly the wall blends into your landscape. If your yard gets a lot of water, avoid timber; for small decorative tiers, modular blocks are both affordable and beginner-friendly.

Materials and Tools Checklist Before You Start

Before you even mark the ground, it helps to gather everything you’ll need. Nothing slows a project more than realising you’re missing a drainpipe halfway through the build. Over time, I’ve built my own “go-to” checklist that keeps the entire process smooth from day one.

Materials

Here’s what you’ll need to build a solid, long-lasting retaining wall:

• Concrete blocks or stones: Choose based on wall height and design.
• Gravel: For both base and backfill; helps with drainage and stability.
• Geogrid fabric: Adds reinforcement between layers for extra strength.
• Perforated drainpipe: Carries away trapped water from behind the wall.
• Landscape adhesive: Secures top blocks or caps.
• Leveling sand: Ensures an even foundation.

Pro tip: Always buy 10% extra of your main material to account for breakage or miscuts.

Tools

You don’t need expensive machinery—just the right basics to make the work easier and precise:

• Shovel and wheelbarrow: For digging and moving gravel or soil.
• Level and string line: To keep every block perfectly aligned.
• Plate compactor: Compacts soil and gravel for a stable base.
• Masonry saw or chisel: For trimming blocks where needed.
• Gloves and eye protection: Don’t skip these—you’ll be dealing with sharp edges and heavy materials.

Getting your materials ready ahead of time isn’t just smart; it’s what separates a clean, straight wall from one that slowly starts leaning a few months later. Think of it as setting yourself up for success before the first shovel hits the dirt.

Step-by-Step: How to Build a Retaining Wall (The 7 Steps)

Building a retaining wall might look intimidating at first, but once you understand the rhythm of it—dig, level, stack, backfill—it becomes one of the most rewarding DIY projects you can tackle. Here’s the full process, broken into seven clear, do-able steps that I’ve personally followed (and refined after learning the hard way).

Step 1 — Plan the Wall Layout

Start by marking exactly where your wall will sit. Use stakes and string to outline the curve or straight line of your wall. Measure the height and length so you can calculate how many blocks you’ll need.

• Pro tip: If your wall curves, lay a garden hose first to visualise the shape before marking.
• Keep the layout slightly inward (toward the slope) to add stability.

Step 2 — Dig the Trench and Compact the Base

This step makes or breaks your wall’s lifespan. Dig a trench that’s deep enough to bury the first course of blocks—usually about one-tenth of your wall height plus 6 inches for the base layer.

• Compact the soil using a plate compactor or hand tamper.
• The trench should be wide enough to fit the block and a few extra inches of gravel on each side.
  As one Reddit DIYer put it perfectly: “I skipped compaction once—never again.” The ground shifted, and so did the entire wall.

Step 3 — Add Gravel and Ensure a Level Foundation

Pour about 4–6 inches of crushed gravel into the trench, then compact it tightly. Check that it’s level from front to back and side to side.

• Uneven foundations are the biggest cause of leaning walls.
• Use a long level and string line every few feet for accuracy.

Step 4 — Lay the First Course of Blocks

Set your first row of blocks on the leveled gravel base. Take your time here—if this layer isn’t perfect, everything above it will show the mistake.

• Use a rubber mallet to tap each block into place.
• Check for level after every two blocks.
• Make sure the front faces line up smoothly.

Step 5 — Backfill and Install Drainage Pipe

After the first layer is set, start filling the space directly behind it with gravel (not soil). Lay your perforated drainpipe at the base, sloping it slightly toward an outlet point where water can escape.

• Wrap the pipe in landscape fabric to prevent clogging.
• Compact the gravel gently to remove air pockets.

Step 6 — Stack Additional Courses, Offsetting Seams

Lay the next row of blocks so that each joint sits in the middle of the blocks below—just like brickwork.

• Apply landscape adhesive between layers for extra strength.
• Continue backfilling and compacting gravel after every row.
  This offset pattern adds stability and prevents straight-line cracks.

Step 7 — Cap, Secure, and Finish with Landscaping

Finish your wall by gluing on capstones or smooth-top blocks. Once the adhesive dries, backfill the upper soil and blend it with your garden design.

• Add plants or mulch above to hide the transition.
• Step back, check alignment, and admire what you’ve built.

Once you’ve mastered this project, why not tackle another one? Check out 7 Easy Steps to Fix a Huge Hole in Your Drywall Without Calling a Pro — another rewarding weekend DIY that’ll make your home feel brand new.

You don’t need heavy machinery—just patience and good prep. Each layer you add strengthens the one below, and by the end, you’ll have a wall that looks professional and lasts for decades.

Drainage & Backfill — The Hidden Hero of a Lasting Wall

I can’t stress this enough: drainage is what keeps your wall alive. Most walls fail not because they’re weak, but because water gets trapped behind them, creating invisible pressure that pushes everything forward.

Correct Gravel Layering Depth (12 Inches Minimum)

Always use a minimum of 12 inches of gravel behind the wall. This layer allows water to flow freely instead of building pressure. Compact it lightly in layers as you go up.

Drain Pipe Slope (1 Inch per 4 Feet Rule)

Your drainpipe should slope downward at roughly 1 inch for every 4 feet of length so gravity can do its work. End it in a visible outlet point—either a side slope or a gravel pit.

Avoid Using Soil for Backfill — Why It Causes Pressure

Soil retains water, and water equals pressure. That pressure will bow your wall outward over time. Stick to gravel or crushed stone; they don’t absorb moisture and drain fast.

As explained by This Old House, every strong retaining wall relies on good drainage and proper backfill—not more cement or thicker blocks. Water always finds the weakest point, so plan a way for it to escape before it starts pushing back.

Common Mistakes That Ruin Retaining Walls

Even experienced DIYers slip up on a few basics. These are the errors I see most often—and they can undo weeks of hard work:

• Skipping compaction or leveling: The most common reason walls lean or crack within a year.
• No drainage pipe: Without an outlet for water, pressure builds until the wall fails.
• Using glue instead of mechanical tiebacks: Adhesive alone won’t hold if soil shifts or freezes.
• Ignoring frost line depth: In colder regions, frost heave can lift the base blocks if the trench isn’t deep enough.

Every mistake on this list comes from rushing. Take your time with the base and drainage—it’s slower at first but saves you from rebuilding later.

A retaining wall built patiently isn’t just strong; it’s something you’ll look at every season and feel proud of, knowing it’s both beautiful and built to last.

Budget & Maintenance Tips for Long-Term Stability

If you’re building your own retaining wall, it’s natural to wonder how much it’ll cost — and how long it’ll last. The truth? You don’t need a massive budget to create something sturdy and stylish; you just need smart planning.

On average, a DIY retaining wall costs between $20 and $50 per linear foot, depending on materials and wall height.

Here’s a quick guide to help you plan and maintain your wall long-term:

Yearly Inspection Checklist

Make it a habit to check your wall once or twice a year, especially after heavy rains or frost. Look for:

• Small cracks in the blocks or mortar joints.
• Bulges or leaning sections that might indicate shifting soil.
• Erosion at the base or missing gravel where water drains out.
• Blocked drainpipes, which can trap pressure behind the wall.

If you catch issues early, most fixes are simple—repacking gravel, resealing joints, or tightening caps.

When to Hire a Pro

If your wall will be over 4 feet tall, that’s the point where professional help is a must. Anything above that height usually requires engineering calculations for load-bearing and safety. A licensed contractor can design reinforcements and drainage systems that prevent collapse and meet local codes.

Think of maintenance like insurance for your hard work—small yearly checks can add decades to your wall’s lifespan. And if you’re planning to repaint or refresh nearby surfaces after the project, don’t miss 7 Tricks to Prevent Paint Drips and Mess-Free Walls — it’s a quick guide to keeping your finishes spotless and frustration-free.

Design Ideas to Blend Function with Beauty

One of my favourite things about retaining walls is how easily they blend structure with creativity. Once the functional part is done, you get to have fun with it. A wall doesn’t have to look “industrial” to be strong—it can be the highlight of your backyard.

Here are some design ideas that bring both charm and purpose:

• Add LED lighting strips or solar uplights between blocks or under caps for a warm evening glow.
• Use curved layouts to soften the hard edges and make the wall feel natural within your landscape.
• Combine materials, like stone and timber, for contrast and texture—stone for the base, timber for accents or seating edges.
• Include built-in planters along the top to grow herbs, flowers, or cascading greenery.

Every creative touch you add turns the wall from a boundary into a feature—something that feels like part of your garden’s story, not just a barrier. If you love adding character to your walls, you might also enjoy exploring 5 Accent Wall Trends You Need to Try for a Modern Look — simple, creative upgrades that can give your indoor or outdoor spaces a fresh, modern touch.

Safety, Code, and Permit Essentials

Here’s something many DIY guides skip—building codes and permits. Even though you’re working on your own property, walls over a certain height usually need approval to ensure they won’t collapse or affect drainage in neighbouring yards.

Before you start digging:

• Check your local municipal codes or city website for wall height restrictions. Many areas require a permit for anything over 3–4 feet.
• Call 811 (U.S.) before you dig, so utility companies can mark any underground lines or pipes. It’s free and prevents dangerous mistakes.
• Plan for load-bearing safety. A civil engineer once said it best: “A wall over four feet? Always engineer it.” That single rule has probably saved more projects than any expensive tool ever could.

Following the proper steps doesn’t slow you down—it protects your investment and ensures you can proudly say your wall was built to last and built to code.

Final Takeaway — Build Smart, Not Just Strong

By now, you’ve seen that building a retaining wall isn’t just about stacking blocks. It’s about understanding the ground beneath you, respecting the water above it, and creating something that blends strength with beauty.

When done right, a retaining wall transforms your yard—it doesn’t just hold the earth; it holds the shape of your vision. You’ll step back after the final block, wipe the dust from your hands, and realise your backyard isn’t just levelled—it’s completely renewed.

So tell me — what’s your next backyard goal after building the wall? More garden space, maybe an outdoor kitchen, or a cozy seating corner?

Share your ideas in the comments and join the conversation at buildlikenew.com — where real homeowners turn DIY dreams into reality.

Disclaimer: The information in this article is for general guidance and educational purposes only. Always check your local building codes, safety regulations, and permit requirements before starting any construction project. If your retaining wall exceeds 4 feet in height or involves complex soil conditions, consult a licensed contractor or structural engineer to ensure safety and compliance.