The cheapest way to build a retaining wall is to DIY it. And the most DIY-friendly way is to use commercially available concrete blocks, sold in Home Depot or Lowe’s. They commonly come as self-aligning and trapezoidal in shape which makes it easier to form concaves, convexes, or straight walls. They are lightweight, have flat sides, and easily fit together without having to use mortar. Your main work will be to create a leveled gravel footing and lay the blocks. Some type of anchoring will be necessary – consult at the store. But while this option is one of the easiest to build it can be costly. Still, it’s probably the most aesthetically appealing one, especially as a landscape feature.
To see many other options and to get inspired, check out my great selection of wall designs and inspirational ideas.
For your convenience, I’ve also researched some most common questions and answers about building retaining walls.
They can become pricey very quickly. This guide should help you to discover some cheap and inexpensive retaining wall ideas. The total cost of building a retaining wall is mostly determined by the following four factors. Let’s discuss them.
Residential Retaining Wall Cost Factors
1. Wall Material Selected
For information regarding prices of various wall materials, jump to Costs.
Concrete Blocks and Poured Concrete: Many sites list poured concrete as one of the most expensive materials used to construct a retaining wall. I have a different opinion. If you want the strongest wall then poured concrete is the way to go. If you’re building a small wall (short and low) then going with concrete could be the least expensive DIY method. Yes, it’s very labor-consuming. But that is where you save a lot of money doing it yourself! You dig a trench, you build a form hopefully using some recycled plywood (or buy a few sheets), you buy a bunch of bags of dry concrete, you mix it, you pour it, you lay a few drainage pipes, and you’re done. Of course, if you’re in need of a longer and taller wall, it’ll be lots of pouring and hard work. For that, it’s better to go with a ready mix cement truck which is costly. Then your other cheaper option is Cinder Blocks (concrete blocks with holes). If you want the strength of poured concrete at around half the cost select cinder blocks.
Wood: Wood is a relatively affordable material. Unless you’re building in 2021. Who knows how long will the lumber crisis last. In general, treated for ground contact wood is cheap and can be readily purchased at a lumberyard or home improvement store. Select lumber that is pressure-treated – it will ensure that your wall will be durable and long-lasting. A wood wall 3 to 4 feet in height will only need a simple base of crushed stone and T-shaped deadman anchors. If you can build yourself a raised garden bed using wood you can sure build a retaining wall from wood, just make it sturdier.
Used railroad ties or sleepers would be another great and inexpensive material to build a wall from if cosmetics are not as important. They are sold in lumber stores.
Boulders: For a creative way to build an appealing wall that is inexpensive, use boulders. They’re free if you can find enough of them for your project. Think about the pattern you want to create – the style of boulder retaining wall will determine the size of boulders required for your DIY project. The basketweave pattern will need boulders that are similar in size and shape; the random pattern can use different sized boulders; a boulder wall combining the two previous patterns is constructed of selected random boulders mixed in with mostly regularly sized boulders.
- Wall Height
Build a wall only so high! The higher the wall, the more expensive it will be to build. You can find plenty of cheap retaining wall ideas for designs four feet and under. A pony wall is a great example of a short retaining wall that creates a visual barrier between two landscaped areas. Pony walls and retaining walls under four feet can be dual purpose – landscape feature and provide seating.
If you DIY, of course, the labor is free.
We included a brief outline for building a retaining wall, with an emphasis on when a wall needs some type of drainage system.
DIY Retaining Wall Ideas
While retaining walls have the practical function of holding soil and rain runoff back, they can also be used to increase the visual impact of outdoor space. Could your yard benefit from one but need some DIY ideas?
Gravity walls: A gravity wall is a type of retaining wall that stands up on its own. Constructing one of stacked stones or boulders can be used to create straight, curved, or tiered walls under four feet.