Retaining walls are designed to add extra structural support to keep soil right where it needs to be, preventing erosion and unwanted movement. One of the main purposes is to make a sloped area functional, but they can also improve drainage by directing the flow of water. All this is to say that a retaining wall plays an important role in a property’s functionality and structural integrity, but what happens when a retaining wall is compromised and it begins to lean?
The soil pressure and moisture buildup from behind the retaining wall can eventually cause it to lean. This is more prevalent in older walls that have been exposed to mother nature and have deteriorated over extended periods. Additionally, those with poor construction are known to lean. However, it’s also important to note that some leaning is okay in most situations. It’s highly unlikely that you’ll be able to get the wall pushed back into its original shape, and as long as it’s still structurally sound, it shouldn’t be a problem.
In other situations where a leaning wall moves when you push on it, or the shifting has been considerable enough to raise safety concerns, you’ll need to consult with a professional for a replacement because this kind of lean means the wall is significantly compromised. Let’s look at the common reasons your retaining wall is leaning.
1. Improper Drainage
If your retaining wall has insufficient or blocked drainage, it can lead to severe problems. When water pools or is held atop or within the retaining wall, it can cause the wall to bulge or even force the bricks or sleepers out of alignment. While it seems like a far reach, the water resting above your retaining wall can cause it to lean the wrong way too. Drainage needs to be considered in all stages of the planning and construction processes. This includes ensuring a proper gravel backfill is installed with the wall. When you work with a team like ours, that is experienced in constructing retaining walls including large complex ones, you are in good hands because they’ve seen it all before and have developed problem-solving abilities to tackle even tricky terrains, slopes, and spaces. Choose local Northern Beaches fencing contractors and landscapers to get the job done to the highest standard possible.
2. Soil Type and Reactivity
Even if you carefully and meticulously designed your retaining wall with the ideal drainage and the proper gravel backfill was put in place, the soil can begin to shift behind and beneath it due to excess moisture. As the soil takes on moisture, it expands. If the temperature fluctuates significantly, it will expand even more, causing greater shifting. Some soil is more reactive than others, you’ll find clay-based soils are very reactive, meaning that they swell and shrink regularly to weather changes, especially moisture levels. Knowing the local soil types is very important in all things landscaping, including retaining wall construction.
In addition to the weather causing these problems, if you have plants near the retaining wall and water them frequently, it can add to the swelling conditions of the soil. A best practice would be to spread out the watering schedule as much as possible to avoid oversaturating the ground. Or better off, clear the area before the wall is built, to ensure no roots damage the structural integrity as they grow.
3. Subpar or Inappropriate Material Choice
Choosing the wrong materials for the job can lead to your wall leaning, just like you have fencing problems when you choose sub-quality fencing materials. Investing in high-quality, treated materials that are designed for end use, will be able to withstand the conditions including moisture and pressure that a retaining wall will face on a daily basis. See splits in the timber sleepers your current retaining wall is showing? This could be a sign that the timber used wasn’t of high quality, or wasn’t treated correctly, this will lead to costly replacements and an all-round headache for you.
4. Shallow Posts
The supportive posts need to be driven in at an acceptable depth. This ensures the most support is provided to the entire retaining wall. If the posts are at a shallow depth, they don’t have the foundation needed to keep the wall in the right position, allowing it to lean. This error in construction can be avoided when hiring a reliable contractor who knows what they are doing.
5. Unstable Fluctuation with the Weather
As the weather fluctuates, the soil can undergo changes in expansion and contraction. With rain, as we mentioned, it expands. Then, with frigid temperatures, it expands further. However, if the weather suddenly takes a turn and becomes beautiful with the ground thawing, the soil will undergo rapid shrinking. All this takes a toll on your retaining wall and can cause it to lean dramatically.
6. General Passage of Time
Over time gravity will make itself known in the leaning state of your retaining wall. The weight of the soil behind it is continuously pushing against it. Older walls are much more likely to lean than newer walls because of this. However, good construction goes a long way toward preventing this from happening any time soon. A solidly built retaining wall with adequate drainage will last a surprisingly long time. Invest wisely and you’ll reap the reward for decades.
7. Building on Top of Your Retaining Wall
Most backyard retaining walls are not designed to have any type of construction built on top of them. The materials are not designed to hold the weight. At best, it will cause mild leaning. However, any kind of construction on top of your retaining wall can result in the wall’s ultimate failure. Considering that it’s holding back a significant amount of soil or other material, this can be absolutely catastrophic. This is why, if you plan to build anything on top of a retaining wall, it needs to be part of the design, planning and construction process, to account for the weight it needs to hold.
The best way to ensure you get the best longevity out of your retaining wall is to work with an experienced team that has a proven track record of their work and the longevity of it. Give us a call today to book in your free quote.
