Discover the Perfect Retaining Wall Solutions for Your Property
Are your existing retaining walls falling apart? Are you worried about what might happen if your retaining wall were to collapse? Are you wondering what retaining wall solutions are available today and what solution is the best? If any of these questions resonate, you are in the right spot. In this article, we’ll explore the vital role that retaining walls play, identify the most common issues that can plague them, and survey the wide range of solutions available to homeowners and property owners today. Whether you’re grappling with a failing retaining wall or simply seeking to safeguard your property against future damage, read on to discover the best way forward.
When is a retaining wall needed?
A retaining wall is typically needed when the ground on your property is sloped or uneven, and you need to level it out for various reasons. Here are some common reasons why your property may need a retaining wall:
Erosion control: If the soil on your property is prone to erosion, a retaining wall can help stabilize the soil and prevent further erosion.
Flood prevention: If your property is located in a flood-prone area, a retaining wall can help protect your property from flooding by holding back excess water.
Landscaping: If you want to create a level surface for a garden, lawn, or patio, a retaining wall can help you achieve this by holding back the soil.
Structural support: If your property is built on a slope, a retaining wall can provide structural support to prevent soil from sliding down the slope and causing damage to your buildings or other structures on your property.
Overall, a retaining wall can help enhance the safety, functionality, and aesthetic appeal of your property, making it a worthwhile investment.
Common retaining wall problems.
Are you wondering why your timber retaining wall is falling apart? Keep reading to learn the most common reasons for this.
5 reasons why your timber retaining wall is falling apart
Improper or absent drainage is a prevalent cause of retaining wall failure. Water combined with soil can substantially elevate the pressure against a wall, making it vulnerable to collapse. Hence, it is crucial to have a minimum of 12 inches of clear gravel situated behind the wall, separated from the surrounding soil by filter fabric or landscape fabric on all sides. If the joints of the wall are mortared, it is equally important to install a perforated pipe and appropriate outlets to drain away the water. However, despite the importance of these drainage systems, they are often either installed improperly or not present at all.
Too Close to Roots
Over time, the roots of trees or bushes can exert enough pressure to displace a retaining wall. Therefore, it is advisable to build retaining walls at a safe distance from any existing roots. Unfortunately, this rule is often disregarded due to people’s reluctance to remove trees or bushes or their eagerness to create flat spaces with a retaining wall. As a result, retaining walls may become vulnerable to root pressure and eventually fail.
Wall is Too High
Retaining walls that are taller than 4 feet require a different approach than their shorter counterparts. In addition to being built with thicker materials, taller walls must also incorporate geogrid reinforcements to prevent the soil from pushing against the wall and causing it to fail. Moreover, retaining walls exceeding this height must undergo inspection and approval by a structural engineer to ensure they are safe and structurally sound. Unfortunately, many builders and property owners overlook this critical step in an effort to cut costs and expedite the construction process, putting themselves at risk of costly and dangerous consequences down the line.
Retaining walls that are subjected to heavy loads from structures such as houses, sheds, or driveways require a different construction approach than walls that are simply holding back soil. Builders must account for the increased pressure and weight by using geogrid reinforcements and increasing the amount of gravel behind the wall beyond the minimum recommended depth of 12 inches. Unfortunately, many property owners and builders overlook these crucial steps in the interest of saving time and money, resulting in poorly constructed walls that can quickly become overloaded and unstable. In the end, cutting corners on the construction of retaining walls can end up being more costly and time-consuming in the long run.
Terraces too Narrow
When faced with a hill that’s over 4 feet high that needs to be retained, some landscapers may attempt to cut corners by building terraces instead of a proper retaining wall that is approved by an engineer. However, this approach can be problematic if not done properly. To ensure the stability of the terraces, the run or the flat part of each terrace must be twice the height of the wall itself. This is because a terrace that is too narrow puts an excessive load on the wall, effectively making it one long wall without the proper support and engineering needed to withstand the extra height and weight. Neglecting this crucial aspect of retaining wall construction can result in unstable and unsafe terraces that are prone to collapse.
Retaining wall solutions
Now that we have covered what problems you may have with old retaining walls let’s look into what are the best retaining wall solutions.
Pressure Treated Timber
Pressure treated 6″ x 6″ timber retaining walls have been installed throughout Vancouver, the Fraser Valley, and Vancouver Island for decades. Correct installation is the KEY to making timber walls last their full lifespan. This includes the use of horizontal tiebacks with deadmen (which secure the wall to the earth it is retaining) and effective drainage management. The use of soldier piles can also be incorporated to allow walls to be installed where there is minimal access or where it is critical that the landscape behind the wall is not damaged.
Best: This option is the best if you are looking for a more affordable option
Lifetime: 25-30 year lifespan
Cost: mid-range solution
Concrete block retaining walls (the popular Allan Block walls) are the most commonly installed retaining wall system at new construction projects. Not only is it a proven effective method of retaining soil, but it has extreme versatility for conforming to landscape and architectural designs/layouts. It may be considered the most popular retaining wall system in the contemporary world. Concrete block walls also have many color and finish options, which provides a great opportunity for an aesthetically pleasing landscape!
There are several advantages to using concrete blocks for your retaining wall. They are durable and long-lasting, meaning they can withstand harsh weather conditions, fire, and even earthquakes. Secondly, they are relatively low-cost compared to other building materials such as brick or stone. Additionally, they are easy to manufacture and transport, making them a convenient choice for construction projects in remote or hard-to-reach areas.
Correct installation is extremely necessary for this wall to last even though it is concrete. If a gravel base is not packed enough, you will have sinking blocks. If an effective water management system is not put in place, hydrostatic pressure will build after rainfall and collapse an entire wall. Geogrid is the ‘tieback’ system for block walls, and it is primarily required for walls over 4′ high. Walls below 4′ high are typically constructed as gravity walls.
Best: This is the best quality longest lasting solution for retaining walls.
Lifetime: 40 years
Cost: High-costing solution
Why is it vital to repair my retaining wall?
If you don’t care and maintain your retaining wall, cracks and bends could lead to collapse. If that does happen, it will be a huge problem. First, you risk damage to your property if you were to have a collapse. Second, the cost to replace a damaged wall is much higher than doing simple repairs and fixes.
Do I need to call an engineer?
If your wall is typically over 4′ high it needs an engineer drawing and a permit. We can assist with this.
In conclusion, retaining walls play an essential role in providing structural support, preventing soil erosion, controlling floodwater, and enhancing the aesthetic appeal of a property. However, retaining walls can fail due to several factors such as improper drainage, root pressure, excessive height, overloading, and narrow terraces. When choosing the best retaining wall solution, it is essential to consider the cost, lifespan, and effectiveness. Pressure-treated timber walls and concrete block walls are two popular retaining wall solutions. Pressure-treated timber is a mid-range, more affordable option with a lifespan of 25-30 years, while concrete blocks are a more expensive but long-lasting solution commonly used in new construction projects. Whatever solution is chosen, proper installation and drainage management are critical for the retaining wall to last its full lifespan.
Are you worried about the retaining wall at your strata? Call us today to book a free inspection of your retaining wall today.
We hope you found this article to be helpful. Feel free to call or contact us with any questions you may have about fence replacement for your strata, and a member of our support team will be happy to assist you. We pride ourselves on having the best customer service in the industry. We care about our clients and are genuinely grateful for their business. Thank you for reading this.