A retaining wall is a vertical barrier near the base of a slope in the landscape. It works as a dam against the soil stopping the slope at a specific point in the yard. This point might mark where you want to create a flat area in your yard. The retaining wall could be in a place where soil erosion has the worst impact on your yard.
How you can benefit from a retaining wall?
Top Retaining Wall Benefits
- Prevent Flood Control With A Retaining Wall. ...
- Retaining Walls Can Add An Attractive Element. ...
- Provide A Solid Property Boundary Marker. ...
- Slow Down Soil Erosion With A Retaining Wall. ...
- Make Better Use Of Your Available Landscaping Space. ...
- Reduce Potential Damage And Maintenance. ...
- Retaining Walls Can Add To Property Value. ...
What you should know about retaining walls?
What You Should Know About Retaining Walls In simple terms, retaining walls are structures that hold back or retain soil, water, and other materials behind them. While some clients value these walls for the aesthetic benefits they provide, they also serve an important function in a landscape design.
What do you need to know about retaining walls?
- If the total height of the wall exceeds four feet measured from the bottom of the footing to the top of the retaining wall
- If there is any back slope adjacent to the retaining wall
- If surcharge load conditions exist (buildings, roads, vehicle loads or sloped conditions)
- If solid fences are attached or adjacent to the proposed retaining wall
How do I build a short retaining wall?
Retaining Wall Ideas
- Break up a lawn with raised beds, adding new textures, colors and planting opportunities, while reducing lawn maintenance.
- Go beyond a basic flower bed with stair-stepped walls for multilevel plantings.
- Define a patio space while adding planting opportunities. ...
WHY DO retaining walls fail?
The main cause of retaining wall failure is poor drainage. Without proper drainage, hydrostatic pressure builds up behind the retaining wall. Saturated soil is substantially heavier than dry soil, and the retaining wall may not be designed to handle such a load.
How does a retaining wall stay in place?
Retaining walls can be made from wood, bricks, natural stones or concrete blocks. For DIYers, it's best to use concrete retaining wall blocks, which can be interlocking and are heavy enough to stay in place without cement or other adhesive. Interlocking blocks fit together and add extra security to the wall.
What material do you put behind a retaining wall?
Backfill refers to the dirt behind the wall. In order to provide proper drainage, at least 12 inches of granular backfill (gravel or a similar aggregate) should be installed directly behind the wall. Compacted native soil can be used to backfill the rest of the space behind the wall.
How do you make a retaining wall hold back water?
0:042:43How to Build a Retaining Wall for Water Retention - YouTubeYouTubeStart of suggested clipEnd of suggested clipInstall the base course block using best practices roll the fabric in front of the wall to cover theMoreInstall the base course block using best practices roll the fabric in front of the wall to cover the face of the base. Course backfill the entire cut with drainage rock.
What is the most common retaining wall failure?
The number one cause of retaining wall failure is poor drainage. If too much water gets absorbed into the soil behind the wall, the hydrostatic pressure can push on the wall causing it to bow out or crumble.
Do I need drainage behind retaining wall?
Retaining wall drainage is critical. It ensures water does not collect behind the wall, causing it to fail. A quality drainage system collects and redirects rainwater away from the wall. It decreases pressure on the soil around the foundation and within the wall itself, reducing erosion and settlement.
What should you not do when building a retaining wall?
However, if you're confident in your skills to tackle this project, these are the mistakes you should avoid when building a retaining wall.Choosing the wrong material. ... Failing to provide adequate drainage. ... Putting too much weight behind the wall. ... Tackling too much wall on your own. ... Not doing maintenance.
Do you have to put gravel behind a retaining wall?
Gravel Backfill Do you need drainage behind a retaining wall? Yes, which means you need backfill too. This backfill is the soil that's located in the first 12 inches of space right behind the retaining wall in order to have proper drainage, and it can be either gravel or crushed stone.
Does a retaining wall need rebar?
Retaining walls must be stronger than freestanding walls. Insert rebar in the footing when you pour it; this should be done at every three blocks or at intervals specified by your local codes.
Why do you put gravel behind a retaining wall?
Backfill is the dirt and gravel behind your retaining wall that provides your wall with adequate drainage and water redirection. Backfill is a necessary feature of retaining walls because it ensures that there aren't any drainage issues or water pooling behind your retaining wall.
What are the three possible types of failure of a retaining wall?
Types of failure of a Retaining WallFailure by Overturning. Overturning of Wall. In this failure mode, the toe will act as centre of rotation and the wall would deform something like in the above image. ... Failure by Sliding. Sliding of Retaining Wall. ... Failure by Bearing Pressure. Bearing Failure of Wall.
Should water come through a retaining wall?
Retaining walls like yours need to hold back soil as well as the pressure that develops within it as the ground becomes saturated after heavy storms. The water dribbling through is relieving pressure that might otherwise cause the wall to buckle out and collapse and the soil behind the wall to slump down.
HOW DO retaining walls not fall?
The wall can be strengthened by transferring some of the shear force to the base where the wall meets the ground. This can be done by either extending the footing of the base or placing concrete to thicken the base. Installing anchors or tiebacks is another option for extra strength.
What keeps retaining wall blocks from moving?
DO start with a good foundation. Your retaining wall will only be as strong its support system. For a stacked-block retaining wall that's no higher than four feet, a trench filled with three inches of crushed rock will help keep the wall from shifting and settling.
What causes retaining walls to move?
Improve the drainage: as mentioned above, poor drainage can cause your retaining wall to crack or move due to the pressure of trapped water and moisture building up behind the wall. Therefore, enhancing drainage around the wall could be a good way to make your wall last longer.
What causes a retaining wall to slide?
Sliding occurs when horizontal force equilibrium is not maintained (i.e., when the lateral pressures on the back of the wall produce a thrust that exceeds the available sliding resistance on the base of the wall).
What is a retaining wall?
A retaining wall is a vertical structure that holds back soil to prevent erosion and create level areas in a landscape. Retaining walls can be made from a variety of materials including concrete, wood, and stone. Both the construction method and materials will have an impact on the durability and stability of the wall.
Why is retaining wall important?
To do this job successfully, the wall requires careful planning and well-engineered construction. Factors such as soil type, slope size, and weather patterns can all affect the stability of a retaining wall. Having a professional landscape consultant or engineer design the wall will help ensure that you use the right type of wall for your property and that it will hold up to its environment.
How many types of retaining walls are there?
There are four main types of retaining walls, including Gravity Walls, Piling Walls, Cantilever Walls, and Anchored walls. Each type has its strengths and benefits.
When constructing a retaining wall, should the location of utilities be taken into consideration?
The location of utilities should always be taken into consideration when constructing a retaining wall. If the utilities need to be accessed in the future, the design of the wall will have to accommodate future digging.
What is cantilever wall?
Cantilever walls are similar to gravity walls, but they also feature a base slab that extends back into the ground. The base slab uses the weight of the soil and backfill material to stabilize the wall. Anchored walls use tension supports, that are anchored to the soil or rock to support the wall and resist pressure. The anchors can also be combined with other types of retaining walls for additional support.
What Is a Retaining Wall?
Simply put, a retaining wall is a structural feature that allows you to support your landscaping and help prevent erosion. In hilly and mountainous terrain, retaining walls can be used to provide flat grades or even terraced spaces for gardening or recreation—or simply to make your home’s outdoor living space more family-friendly.
Why is retaining wall important?
If you live in a moist or flood-prone environment, a retaining wall can be essential for preventing your soil from washing away. That means that retaining walls aren’t always about aesthetics. They are also often a matter of safety.
How much does it cost to build a retaining wall?
If you choose to install a retaining wall, though, you should budget accordingly. The cost of a retaining wall can range from $3,000 to $9,000, depending on the size, materials, and location.
Can you use retaining walls for outdoor living?
Best of all, you can use retaining walls to make mini-terraces expressly suited for all the purposes your outdoor living space serves. Whether it’s cookouts, toasting marshmallows around the fire pit, or relaxing in a lounge chair with a good book, hardscaping with strategically-placed retaining walls can provide ideal dedicated spaces for them all.
Do retaining walls add visual appeal?
You don’t have to be worried about your yard and home slip-sliding away to benefit from a retaining wall, though. Retaining walls can add tremendous visual appeal to your home’s exterior.
Do you have to build a fortress to get a retaining wall?
You don’t have to build a fortress to get a retaining wall that works. Even a low wall can serve its purpose well.
Is it cheaper to regrade a yard than to install a retaining wall?
There are other options, of course, if erosion is a concern. On average, it costs less to regrade a yard than to install a retaining wall. But the tradeoff is that the earth moved during regrading will likely continue to shift, meaning you may end up repeating the process all over again. Plus, unlike a retaining wall, you don’t have the structural reinforcement of earth and soil as you do with a stone, steel, brick, or concrete wall.
What happens when a retaining wall saturates?
When it saturates clay-type soils, they swell and put excessive pressure on the backside of the wall. To avoid failure, make drainage provisions at the same time as you go about building the retaining wall.
What materials are used to build retaining walls?
Retaining walls can be constructed using a variety of materials, from poured concrete and large timbers to natural stones, even bricks. For DIY purposes, opt for manufactured blocks that are designed specifically for building retaining walls; a locking flange along the bottom edge creates a secure attachment between rows.
How deep should a retaining wall be?
The exact depth of the trench depends on the proposed height of the wall, but follow this rule of thumb: Dig a trench to be an eighth of the wall plus three inches. For example, if you want the finished height of your retaining wall to be three feet (36 inches) tall, you’d need to dig the trench eight inches deep to accommodate three inches ...
What does a perforated drain pipe do?
The perforated pipe will carry groundwater to each end of the wall where it can drain harmlessly away. The ends of the drainpipe should then exit on each end of the wall, and you may cover them with crushed stone to camouflage their appearance. RELATED: The 10 Best Things You Can Do for Your Soil.
How much soil pressure does a retaining wall need?
Soil is heavy, especially when soaking wet from a recent rainstorm, so a basic retaining wall (four feet tall and 15 feet long) potentially has to support up to 20 tons of soil pressure.
Can you build a retaining wall short?
Shorter retaining walls, however, can be constructed by enthusiastic do-it-yourself ers equipped with some basic construction knowledge. Does that sound like you? If you’re looking to get your hands dirty and enhance your landscape with a retaining wall, these guidelines for building a retaining wall will help you get off to a good start.
Why do we need retaining walls?
A retaining wall is intended to hold back soil when there is a drastic change in elevation. Often retaining walls are used to terrace yards that originally had a steep slope. Additionally, retaining walls can help create usable outdoor space as well as control erosion, (see Landscaping a Split-Level Home .) Low retaining walls are frequently used ...
What happens if water goes unaddressed behind a retaining wall?
When drainage goes unaddressed hydrostatic pressure will build up behind the wall and cause damage such as bulging or cracking. There are a number of ways to ensure proper drainage of water from behind a retaining wall. First, is to make sure your landscaping contractor backfills at least a foot of space behind the wall with gravel.
What is a backfill for retaining walls?
Backfill. Second, a retaining wall must have properly compacted backfill. Backfill refers to the dirt behind the wall. In order to provide proper drainage, at least 12 inches of granular backfill (gravel or a similar aggregate) should be installed directly behind the wall.
How high should a retaining wall be?
Typically, residential retaining walls are built between 3 and 4 feet high.
What is the best base for a wall?
The taller a wall is, the further below ground level it should be set. Crucial for supporting the rest of the wall, a good base is made of compacted soil and at least a six inch layer of compacted sand and gravel.
Why do retaining walls fail?
Retaining walls are useful and attractive features in many yards, but they are prone to failure if proper drainage is not considered. Some professional installers find that nearly 80 percent of the retaining walls they see fail at some point due to improper drainage. Whether you are planning to install your own retaining wall or have someone else ...
Why is drainage important for retaining walls?
Why Proper Drainage is Important for Retaining Wall Performance. A retaining wall is built to hold back a certain amount of soil. The design of a properly-built retaining wall resists the force of the soil behind it and prevents caving, buckling, or leaning. However, retaining walls are built with a certain capacity in mind.
What is the backfill for retaining walls?
Backfill simply refers to the soil directly behind the wall. For proper drainage, the first 12 inches of space behind a retaining wall should be filled with crushed stone or gravel. This is so that when water gets into the space, it does not become bogged down in soil but instead can flow down the wall to the drains or weep holes. Many designs allow for the top six inches of space behind a wall to be filled with native soil, so that the area can be used for planting.
What is a weep hole?
Weep Holes. Weep holes are openings in the front of the wall that allow moisture to escape. They may be positioned at the base of the wall for structures with minimal need for drainage, or in a grid pattern across the entire wall. Water flowing from weep holes can create unsightly stains if the retaining wall material is not properly protected, ...
Why is compaction important?
Soil compaction is most important for creating strength , but it also makes the dirt less permeable and reduces the ability of water to seep into the space behind the wall. The soil behind the layer of gravel backfill is the target for this step.
What happens when water gets behind a wall?
When water gets behind the wall, it puts additional pressure on the structure, which can result in the overall force exceeding the wall’s ability to resist. This is what good retaining wall drainage looks like: When the wall is no longer able to resist the force behind it, the weakest part will give.
Why does a wall buckle?
In other cases, water pressure behind the wall may cause it to lean outward. If the pressure is consistent and forceful enough across the wall, it may even buckle.
