Retaining walls are a popular addition to properties here in Texas, as they’re highly functional and hold back dirt that could otherwise erode without it. These walls also help to create flat, usable spaces, and you can use various materials to build them, including concrete, brick, natural stone, and wood. However, all of them need footing, and the type of footing depends on the height and materials you use for the retaining wall. Proper drainage is another crucial factor, as water buildup can compromise its structure and cause extensive damage. Cost is always something to consider with hardscape features like retaining walls; how much it’ll cost depends on how high you build it and what materials you use. Continue reading to learn more about all the basics of retaining walls!
What are the functions of retaining walls, and what materials can you use to build them?
Retaining walls are functional features that reduce erosion by holding back dirt and soil. These walls can hold back anything from rock falls and hills on the sides of highways or roads to something smaller like a landscape bed. However, that’s not all they can do – retaining walls also help to level out and create flat space, making them great for properties on a slope or with a steep incline. That way, you can use that land for a patio or, on a larger scale, a shopping mall, school, or building. They can even pair well with fences to make steep drops safer, create planting beds, terracing, and walkout basements, then function as retainers for landscaping, statues, trees, and stairs.
Retaining walls are customizable in the materials you can use to build them, and you can choose which suits your aesthetic preferences and needs. For example, you can opt for wood, giving it a more rustic, earthy look, or masonry materials like brick, paver blocks, natural stone, or concrete.
Some structural retaining walls require building permits, so it’s always important to check with your local building department before installation to see if you need one.
What are footing options for retaining walls?
Footers help to keep retaining walls stable if the ground below shifts, preventing it from possibly collapsing. All walls need a footing, but what type depends on their design, materials, height, weight, how much it retains, soil conditions, and the weather. There are two common types of footing, which are as follows:
Concrete Footing: This footing is best for retaining walls built from large masonry materials like concrete, cement, or brick. These materials are stiff and don’t easily flex with movement, instead cracking and potentially leading to structural failure. So, they need a strong, stable foundation to hold them together. Creating concrete footing involves digging a deep trench to allow it to sit below the frost line, as shallow ones can cause movement if the soil freezes, then pouring at least 12″ to 16″ wide by 1 foot deep of concrete atop compacted gravel, which should be a few inches thick to provide some drainage. However, the right size depends on the materials, soil, and site conditions.
Crushed Compacted Stone Footing: This footing is ideal for retaining walls built from loose rocks, wood, stacked stone, paver blocks, large stone, or bricks without mortar. These materials can flex a little, as they aren’t held together by concrete or mortar. When the crushed stone footing is properly compacted, it’s highly durable, won’t settle, and offers some drainage. However, the height of the wall determines how much it needs; for example, if it’s 4 feet tall, it generally needs footing 8″ to 10″ with a depth of at least a foot below grade, going up as the height increases. Even for a simple, single-layer border wall, you’ll still want to have at least some compaction.
You’ll want to ensure your retaining wall has proper drainage.
Proper drainage is the key to a long-lasting retaining wall because water can create pressure underneath and behind it, leading to shifting, cracking, buckling, structural failure, and possibly even causing it to collapse. So, you’ll need to place drainage at the footing and directly behind the wall to divert water away from it; the former needs it to prevent water from swelling under or around it, while the latter requires drainage pipes and rocks to carry it away and stop it from collecting behind it.
Stacked retaining walls don’t usually experience drainage issues because water can drain through the blocks, relieving some of that pressure. However, you’ll still want to put a porous fabric behind a dry stack wall to prevent the dirt from flowing with the water that drains through the joints. On the other hand, solid retaining walls don’t allow that same drainage through the blocks, so it’s crucial to give them proper drainage.
Another thing to consider with drainage is the height of the retaining wall. As it gets taller, it becomes more susceptible to water damage. Because of this, one over 3 feet requires a footing and wall drain. Meanwhile, a lower build needs at least a footing drain or weep holes; these are 1/2″ to 1″ diameter holes drilled every 10-15 feet to allow for low-volume moisture release.
You’ll want to use gravel as the backfill for your retaining wall, as it doesn’t absorb water and is where you’ll also install the footing drainage pipes.
How much your retaining wall will cost depends on the materials you use and its height.
Cost is always something to consider when building a retaining wall. How much it’ll cost depends on the materials you use; for example, wall blocks are cheaper, equating to around $1.00 to $5.00 per block, depending on their size and design. Natural stone is another common material, namely limestone cut block, which can cost anywhere between $40.00/per face square foot to $80.00/per face square foot.
The height of your retaining wall is another factor in how much it’ll cost. A smaller one up to 3 feet tall can cost an average of $15.00 to $40.00 per face square foot if you build it yourself. Meanwhile, large walls cost more because of the labor involved. A natural stone or brick retaining wall can cost $20.00 to $50.00 per square foot; the more skilled labor involved, the more expensive it’ll be. However, the footing can also contribute, as concrete is more costly than crushed compacted stone.
Call Us to Schedule Our Retaining Wall Installation Service Today
If you want to install a retaining wall on your property, you’ve come to the right place! Our team at CLC Landscaping has all the training and experience to install it right the first time, providing the correct footing and proper drainage to ensure it’s long-lasting. We also offer various material options you can choose from, and we’ll always be transparent with your costs to stay within your budget.
We offer our retaining wall installation service to residential property owners in New Braunfels, Buda, San Marcos, TX, and other nearby areas. Call us at (830) 243-6805 to schedule today!