Your Backyard Retaining Wall is Failing — Here's What to Look For
Though they often go unnoticed, retaining walls are the unsung heroes of backyards. They do a lot of physical labor, such as holding back tons of dirt, fighting gravity or dealing with every thunderstorm that hits. Like almost everything else in a home, they need occasional maintenance.
Fortunately, your wall will likely show signs of struggle before it collapses. If you know what to look for, you can take the right preemptive measures.
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Why Your Wall is Falling
Backyard retaining walls hold back soil on a slope to create usable land and manage erosion. They can also help protect foundations and manage drainage. With the retaining wall market projected to reach $8.7 billion by 2033, understanding how to upkeep yours can be an excellent investment for your property.
People often think a falling wall is due to bad blocks or rotting wood, but the underlying problem is often beneath and behind the wall. Soil is heavy enough when dry, and even heavier when wet. When it rains, the soil absorbs the water like a sponge, expanding and pushing your wall outward and over. This is known as hydrostatic pressure.
The ground underneath the wall is another significant factor. If the foundation wasn’t packed down properly or if the dirt has naturally shifted, the wall will move. For DIY enthusiasts, this means building structures to accommodate the foundation soil settlement, which is the natural way the earth sinks and shifts over the years. If the wall doesn't have the right foundation to handle movement, it eventually breaks,
4 Must-Know Red Flags
The best way to fix a wall is to keep it from falling in the first place. When routinely inspecting your backyard retaining wall and drainage, look out for these specific signs.
1. The “Belly” or Bowing
Stand at one end of your wall and look down the line. It should be straight. If the middle section bulges like a belly, there might be a problem. Bowing usually indicates that the dirt behind the wall is pushing harder than the wall can handle. In a wooden wall, this might mean the timbers are rotting or snapping. In a stone wall, it means the internal structure is giving way.
2. The Leaning Tower Effect
A wall should either be perfectly vertical or tilted slightly back into the hill. If yours is leaning forward toward your lawn, then it’s most likely losing its grip. This usually happens when the foundation at the bottom has been washed out, especially if it wasn’t deep enough to begin with.
3. Separation Anxiety
Check the corners and the spots where the wall meets your house or stairs. If you see gaps opening up, then the wall is physically walking away from its anchor points. Cracks in the actual blocks or concrete, especially vertical ones, must be promptly addressed. They usually indicate that the ground is sinking in one spot but not another.
4. “Weeping” and Muddy Bases
Does your wall stay wet for days after the sun comes out? Do you see white, crusty stains on the stones? That’s “efflorescence,” and it’s a sign that water is trapped inside the wall with nowhere to go. Without weep holes to let that water out, the pressure will keep building until the retaining wall cracks open.
Should You DIY or Call a Professional?
Deciding whether to grab your work gloves or your phone to call a contractor is the big question when it comes to failing retaining walls.
Safe DIY Solutions
Most individuals can handle surface-level maintenance themselves, such as clearing dirt and mulch from clogged weep holes to allow the water to drain. Make sure the dirt at the top isn’t washing away and exposing the back of the wall. Moving your gutters so they don’t dump a large amount of water right behind the wall is another easy win. You can even glue a single loose capstone back down with construction adhesive if it hasn’t affected the main structure.
Seek Professional Help
However, there is a point where “fixing it” becomes dangerous. If that wall has tilted or bowed more than an inch or two, then it’s usually past the stage of a simple patch job. Once a wall gets taller than three feet, the physics change, and you’re dealing with massive amounts of weight and pressure that can cause further property damage or even injury upon collapse.
If you see large horizontal cracks or if the wall is sinking into the ground, there is most likely a foundation issue that usually requires professional help. Contractors have expertise and machinery to safely and efficiently fix a retaining wall.
Proactively Caring for Your Garden
Being a homeowner is about staying one step ahead of the weather. By catching these red flags early, you can ensure your backyard remains a safe, beautiful place for you and your family.
