Many people make the mistake of assuming that a retaining wall is only built to hold soil back for lots on a slope. While that is one of the more common reasons a homeowner decides to have a retaining wall built, it is not the only reason. If you are considering having a retaining wall built at your home, here are some of the things you need to know about them.
Different Types of Retaining Walls
One of the most important things to know about retaining walls is that they are not all the same size or style. All of them are not made from stone, either. Here is a quick look at some of the more common types of retaining walls that people have built around their homes.
- Brick: A brick retaining wall is often used on hillsides to help hold the dirt back. They serve their purpose well but are not as strong as a concrete gravity wall. The one downfall to a brick wall is that the buildup of water pressure can cause them to fail.
- Gravity Wall: This is similar to a brick wall as it is most often used on hillsides. It is typically built with concrete and stones to hold back large amounts of dirt. The sheer size and weight of these walls allow them to work well, but they are easily destroyed in earthquakes.
- Anchored: These walls use cable ties anchored into the ground behind them to increase their strength. This style is particularly useful for high loads of dirt.
- Sheet Pile: These retaining walls are constructed from wood or steel planks. Part of the planks is pounded into the ground to a specific depth to reinforce the wall’s strength.
Purpose of Retaining Walls
Retaining walls serve various purposes, not just to hold back a bunch of dirt on a hillside. These walls are often constructed to help protect shorelines from erosion. They can also be used to help create enough space in an area to install storm drains.
Many people don’t realise that these types of walls are often constructed to support highways and bridges. Retaining walls not only hold back dirt but slow down erosion and offer amazing protection from flooding.
Common Materials Used in the Construction of Walls
Stone, brick, wood, and concrete are some of the most popular materials used for retaining walls. If your budget allows, we recommend using stone, which is worth the expense due to its superior strength and unique appearance.
Brick and wood, on the other hand, are low-cost options. When it comes to brick walls, you should be cautious since they require a solid structural base to ensure that they can hold the weight. You should also keep in mind that they have a shorter lifespan while lumber is less expensive.
When You Need a Retaining Wall
Certain circumstances require you to build a retaining wall on your property. Other times, they are just for appearances. People who are trying to control downhill erosion require the use of a retaining wall. The wall will slow down erosion because it changes the slope of the hills and helps hold soil in one place.
Those who live on the downhill side of a soil fault line should also invest in a retaining wall. These fault lines are similar to earthquake ones. Once they become active, the soil shifts and flows downhill until something stops it. Without a wall in place, the soil’s only chance of stopping is right into your home.
These walls can also help protect your home’s foundations. These walls can help if the soil is breaking away from a downhill foundation due to erosion. They can also help protect uphill foundations that are facing compaction from soil packing up against it.
Does Height Matter?
With all retaining walls, height does matter. For walls that are less than 1.3 metres tall, a contractor is not necessarily needed but one is recommended. If you are going taller than 1.3 metres, though, you want to hire professional retaining wall builders. Not only will they take care of the building of the wall, but they will also design the layout to the specifications required.
Over 1.3 metres requires the use of professional contractors because the taller walls can hold more weight behind them. The wall must not only be designed to support the weight of the materials used for building, but it also has to be able to hold the weight of the dirt pressing up against it. Nobody wants to have a mountain of dirt come spilling into their backyard because the retaining wall collapsed under the weight that it was supposed to hold.
As with the taller walls, lower ones must also be built to hold back the dirt behind them. The difference between them, though, is there is less gravity pushing on the dirt behind the lower wall. Both walls serve a dual purpose. They add interest and beauty to a yard while holding back a bunch of dirt.
Do You Want a Curved or Straight Retaining Wall?
When people think about walls, they tend to think about the straight walls inside their homes. They mistakenly assume that, as with the walls inside their home, their retaining walls must be straight. The good news is no rule or regulation states that all retaining walls must be straight. Many people like to add gentle curves to their walls to give their yards a different look.
Not only can you decide between straight or curved walls, but you can also incorporate a variety of different heights across your landscape. Another option you have is to create a tiered wall, which features numerous walls all at different heights. Many people dealing with a sloped landscape choose the tiered approach as it helps open up unused space.
What Size Stones Are Required?
In most cases, when it comes to building retaining walls, the taller the wall is, the bigger the stones. You want the stones to be proportional to the wall being built. The good news, though, is regardless of the size of stones being used for the build, homeowners still have a few choices in what stones to use.
Some people prefer symmetrical stones. They like the uniform appearance they create. When building a symmetrical retaining wall, stones of the exact same size and colour are used throughout the entire wall.
Other stone choices include a bunch of small stones that are placed close together. These stones are placed tightly together and piled up to form the perfect retaining wall. Another option is using different colours and shapes of stones to create a wall with far less structure. When building a retaining wall, the point is to design and build one that works for your landscape and is visually appealing to you.
Before construction on the retaining wall starts, the area must be dug down below grade. Once it has been dug down a few centimetres, it must be compacted and levelled. If any filler is required, it will need to be added before the stones, bricks, or other materials are placed. This is crucial because it is what builds the foundation of the wall and helps give it its structure.
Water Can Weaken the Walls
Any water that collects behind the retaining wall poses a serious threat to its integrity because it increases the pressure behind the wall. The more pressure placed on the wall, the higher the risk of the wall failing. To prevent failure, your best chance is to ensure adequate drainage around the wall, including drainage sheets to help protect the wall’s foundation.
Another option is to drill some weep holes in the wall. This will enable the water to escape rather than gather behind the wall. Installing a drainage pipe beneath the wall is also a viable option, either near the footing or higher. It’s critical to utilise granular rather than cohesive clay soil as a backfill since water will be able to access the holes or pipes instead of collecting.
Add on a Few Extra Features
Nobody said that a retaining wall has to be plain or boring to look at. While some of them are already adding beauty to your landscape, this doesn’t mean that you can’t add any extra features to make your wall even more pleasing to look at. Some of the extras that you can have built into your retaining wall include building steps in the wall so you can access different parts of your yard. The steps can serve as “shelves” for pots of flowers or any other yard décor.
Another idea includes building a fire pit area in front of the wall, so the back serves as a backdrop for your gathering place. Waterfalls or water fountains also incorporate themselves really well into walls built in your backyard. The point we are making is that adding these extra features helps you create a unique, relaxing place in your yard where you can gather with friends or family.