If you want to prevent erosion or create a multi-tiered lawn, a retaining wall is a great way to do it. But if you’re going to build a retaining wall on your property, it’s important to know what you’re doing. And that’s doubly true if you’re working on a budget. So, how do you build an affordable retaining wall in your yard?
Retaining walls can be built in many ways. Materials range from cheap gabions to decorative wood. Walls themselves can enclose anything from a small garden to a corporate campus. The exact method of construction depends on the budget, the scope of the project, and the purpose of the individual wall.
That said, you might be surprised at how many materials you can choose from. Whether it’s simple concrete, stone, or even reclaimed railroad ties, there are plenty of options for your wall. Here are nine different ways to build your own backyard retaining wall, without breaking the bank. What is the Purpose of a Retaining Wall?
The purpose of a retaining wall is to create a barrier, with the ground level higher on one side than on the other. Generally, they’re used when your property is on a grade. They can be used to prevent erosion, since they keep soil from moving downhill. They can also be used to transform a hillside into a series of flat, terraced tiers.
Some retaining walls are smaller. For example, you might have a large, raised flower bed on part of your property. In this case, the wall basically functions as an oversized planter. Other applications can be very large – for example, enormous retaining walls around freight depots. Thankfully, that won’t be an issue on your lawn.
Things to Consider When Building a Retaining Wall
The Overall Size
When you’re building your own retaining wall, the overall size of the project is a major concern. If you’re looking at running hundreds of feet of wall, you need to consider the amount of time you’re investing. Unless you’ve built a lot of walls in the past, that’s not something you’re going to get done in one weekend. And even if you are, you’ll need a couple of helpers to get the job done.
Larger walls also present additional challenges. You may be working on a slope, and need to run multiple overlapping courses. Not only that, but on any wall longer than 20 to 25 feet, you may need to install a drainage system. This can be done affordably, but you still need to know what you’re doing.
What it Will Cost
The cost of a retaining wall is highly variable. The most significant difference will be the cost of labor. If you’re doing it yourself, that cost is zero. You can invite some friends, buy them each a pizza and a six pack, and you’ve got your labor covered. On the other hand, if you’re paying a professional, you’ll have to cover that expense.
The other factor to consider is the cost of material. Some costs are going to be more or less consistent. For example, you’ll need a proper gravel base, and you’ll have to rent a tamper. But the wall material itself can range from $5 per square foot for cheap gabions, all the way up to $125 per square foot for the highest-grade steels. As you might imagine, this also presents a major opportunity for savings.
A retaining wall needs to be constructed with an eye to safety and longevity. The ground where it’s placed needs to be properly graded, so the wall will have a solid foundation. It needs to be drained, so water won’t undermine the wall, or pool up at the top. If this isn’t done correctly, your wall might collapse. At the very least, it won’t last as long as you’d like it to.
Does the Design and Finished Look Matter to You?
A retaining wall is a major part of any landscape. When you’re putting one on your property, aesthetics are a legitimate concern. Then again, less attractive, more affordable materials have their place, depending on your application.
9 Cheap Ways to Build a Retaining Wall In Your Yard
1. Lumber Retaining Wall
Lumber is a tried and true material for building a retaining wall. It has a rustic aesthetic, and can be left with a natural finish, or stained to a color of your choice. If you’re going to use lumber, make sure to use a pressure-treated wood that’s rated for ground contact. Otherwise, the wood will decay much more quickly.
Since pressure treated lumber can get expensive, many people use repurposed railroad ties, which are much more affordable. Railroad ties are the appropriate grade of lumber, so you know they’re going to last.
2. Gabion Walls
A gabion is a rectangular mesh basket, made with heavy-gauge weather-resistant steel. When the baskets are filled with rocks, they can be stacked on each other like bricks. They range in length anywhere from 3 to 12 feet, and you’ll probably be using 3 or 4 ½-foot gabions for most residential applications.
Gabions are cheap, and the porous design allows for plenty of drainage. There’s no need to install any additional drainage system. On the downside, most people consider gabions ugly, although you can mitigate that by planting shrubbery around them.
3. Pouring Concrete
A poured concrete wall has a number of advantages. For one thing, it’s a strong material by its very nature, and can last for over a century. For another thing, you can customize it by applying a texture, adding a dye, or even sticking rocks or seashells into the surface. And a plain, smooth wall presents a simple, modern appearance.
The downside of poured concrete is that you have to construct forms first, in order to shape the concrete. And if the wall is taller than four feet, you’ll have to pour your footings separately. This requires additional expertise.
4. Dry Stack Retaining Wall
A dry stack retaining wall is one of the most affordable options of all. In fact, it can even be free. You just find a bunch of rocks, old bricks, and slate. Then, you stack this material up into a wall. Not only is this insanely affordable, but you don’t have to dig below the frost line. Because the individual stones can shift slightly, the wall will remain stable during the freeze/thaw cycle.
The downside of a dry stack wall is that you have to stack all the stones so they fit together well. This requires painstaking effort. In some areas, it’s even hard to find contractors willing to do the job.
5. Mortar Retaining Wall
A mortar retaining wall is a modified version of the dry stack retaining wall. You simply stack up your stones loosely, then apply a high-quality type-S mortar to the outer surfaces. Because the mortar provides integrity, you don’t need to be as careful about stacking up your stones.
6. Stacking Large Stones or Concrete Blocks
Concrete and stone blocks are some of the most popular retaining wall materials. They’re available in many colors and textures, so they can fit just about any property. They’re also easy to manage for DIYers, at least compared to other materials like concrete and dry stacking.
Stone, brick, and concrete block walls are generally cheap to have installed. However, because they’re not very porous, you can run into trouble with drainage. On longer walls, you have to install drain pipes.
7. Corrugated Iron Walls
Corrugated iron is a popular material for smaller retaining walls. You can build a wooden frame, put corrugated iron or galvanized steel inside the frame, and build sections of wall to put into place. For an even sharper look, you can anchor the sections into a concrete foundation.
There are also heavier-gauge metals that are specially engineered for use as walls. However, these are extremely expensive, and only used in commercial or government installations.
8. Log (Timber) Retaining Wall
A log retaining wall is a twist on the standard wooden wall. Wood can potentially be free, if you’re using timber from your own land. But most people opt to use lumber that has already been at least somewhat processed.
Another advantage of buying your wood is that you can get pressure-treated timbers instead of untreated. This will get you a lifespan of over 40 years, around double what you can expect from an un-treated wall.
9. Stack Old Tires
Tires are easy to get for free, since it actually costs money to get rid of them in most states. If you’ve got access to a large number of them, you can build a wall with just some dirt and a tamper. Fill the tires with dirt, tamp it down hard, and you’ve got a large, solid disc. From there, you stack the tires just as you would with bricks or blocks.
To build the wall safely, each stage of tires should sit three inches back from the one below it. This will ensure that the wall doesn’t fall over. Keep in mind that a tire full of packed dirt can weigh as much as 300 pounds. You’re going to need some help getting them into place.
The Average Cost of Different Retaining Wall Materials
Here are the average costs for various retaining wall materials. Keep in mind that these ranges represent the very cheapest and very most expensive options. In most cases, you can expect your costs to fall somewhere in the middle.
- Wood – $10 to $50
- Brick – $11 to $17
- Concrete Blocks – $20 to $30
- Gabion Walls – $5 to $40
- Poured Concrete – $30 to $40
- Concrete/Stone Boulders – $27 to $35
- Timber – $10 to $28
- Metal Sheets – $5 to $125 (less than $10 for standard-grade)
Retaining Walls FAQs
How Long Will a Retaining Wall Last?
How long a retaining wall will last depends on what it’s constructed from. Wood and gabion walls will last between 25 to 50 years. Concrete, stone, and brick walls will last from 50 to 100 years.
Keep in mind that a lot of this depends on how well constructed the wall is. If it doesn’t have a good gravel foundation, or if it’s not well drained, your wall isn’t going to last as long. In addition, walls can get damaged by tree roots, which can cause a portion to collapse.
Should You DIY Your Own Retaining Wall?
There are a number of reasons to build your own retaining wall. The most common reason is price, but building your own wall also gives you complete control over the design. That way, you don’t have to wrangle with a contractor to get the exact wall you want. And if you’re a hobbyist, building a retaining wall gives you a great project to work on!
The downside of a DIY wall is that you need to have the right expertise. You’ve got to properly prepare the area, ensure sufficient drainage, and use the right materials for the job. That said, some materials are easier to work with than others. A novice can build a wall with simple materials like blocks and bricks, but poured concrete requires skill with forming, mixing, and pouring cement.
Why Can Retaining Walls Become so Expensive?
The cost of a retaining wall is about a lot more than just the materials. For one thing, you have to dig out a trench for the base. This needs to be leveled and tamped, which means you’ll probably have to rent equipment.
During construction, you can even run into unexpected costs. Rocks and tree roots may need to be cleared, requiring additional labor and expense. Most contractors will build these contingencies into your estimate, but make sure to ask!
As you can see, a retaining wall can be an expensive, time-consuming project, but it doesn’t have to be. If you use the right materials, you can cut down on costs considerably, and still end up with an attractive wall. And if you do the job yourself, you won’t even have to pay for labor. All it takes is time, effort, and a willingness to learn.
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.