Retaining walls can be beautiful, functional additions to any landscape, creating usable outdoor spaces on sloped properties, enhancing curb appeal, and adding value to your home. However, well-designed retaining walls aren’t just about stacking stones or blocks in a visually pleasing pattern.
Behind the scenes, it involves a careful, engineered process that takes site conditions, soil types, and drainage into account. When retaining walls fail, it’s usually due to a lack of expertise in these critical areas—often because shortcuts were taken, or basic engineering principles were overlooked.
In this post, we’ll explain some of the most common reasons retaining walls fail and why it’s so important to hire a knowledgeable, experienced contractor for these specialized projects.
The Top 4 Reasons Retaining Walls Fail
- Ignoring the Importance of Soil Analysis: One of the first steps in any successful retaining wall project is a detailed understanding of the soil types involved. Not all soils are created equal, and different soils have varying drainage and stability characteristics that directly impact how retaining walls should be built.
For example, clay soil is particularly challenging because it retains water and drains poorly. Over time, this trapped water can put extreme pressure on a wall, leading to a higher risk of failure. Sandy soil, on the other hand, drains well and provides a more stable base for footings and wall materials.
For this reason, a reputable contractor will always conduct soil testing to ensure retaining walls are built with the correct materials, drainage, and structural reinforcement based on the unique conditions of the site. Unfortunately, many inexperienced contractors skip this critical step, assuming all soils are the same—often with disastrous results.
- Lack of Proper Engineering and Installation Practices: Every retaining wall requires a degree of engineering to function as intended, particularly when holding back significant amounts of soil or supporting additional structures. However, it’s common for less experienced contractors to cut corners, believing a wall is simply a matter of stacking stones or blocks.
- Underestimating the Need for Drainage: Water is the number one enemy of any retaining wall. In Louisville’s humid climate, managing drainage is even more essential. A well-designed retaining wall includes drainage solutions, such as drainage rock and piping, to guide water safely away from the wall structure. When water isn’t properly managed, it can cause hydrostatic pressure to build up, leading to cracks, bulging, and eventually, total wall failure.
At Landscape Jimmy, we design and install drainage systems for every retaining wall we build—regardless of its size. The complexity of the drainage system scales with the wall’s height and the conditions of the site, but drainage is always essential. Hiring a contractor who understands the value of comprehensive drainage planning can save homeowners from costly repairs and heartache down the line.
- Failure to Use Geogrid Reinforcement on Taller Walls: For retaining walls over four feet in height, Louisville city codes often require an engineer’s plan, which includes specifications for a crucial material called geogrid. This synthetic mesh extends back into the earth behind the wall in layers, anchoring the structure to the hillside and preventing soil movement from undermining the wall. A tall wall without geogrid reinforcement simply isn’t built to last.
Experienced contractors know that a four-foot wall or taller is essentially holding back a powerful force of nature. This is why city regulations mandate an engineer’s stamp for walls of this height—it’s not just a recommendation; it’s a legal and safety standard. If a contractor skips this step, homeowners risk expensive future repairs, potential property damage, and even legal ramifications. Geogrid installation isn’t negotiable for large walls; it’s essential.
Tell-tale Signs of Poor Workmanship
- No Engineering Plans: Some contractors skip the planning stage entirely, leaving critical structural decisions up to guesswork.
- Lack of Precision Tools: The use of hand-held levels instead of professional-grade tools, like laser transits or site levels, often means the wall lacks the precise alignment needed for long-term stability.
- Inadequate Footing Excavation: Rather than using the proper excavating equipment, some contractors dig footers by hand, which results in an uneven foundation.
- No Mechanical Compaction: Compacting the soil behind and beneath a retaining wall is essential for its stability. Without mechanical compaction equipment, which can vary by project size, the wall is likely to settle and shift over time.
- Absence of Drainage: Retaining walls without adequate drainage are ticking time bombs. Poor or nonexistent drainage leads to water buildup behind the wall, increasing pressure and hastening failure.
Each of these shortcuts reveals a lack of understanding of the importance of detailed engineering, which is why hiring a contractor who follows best practices from the start is crucial.
Why You Should Choose an Experienced Retaining Wall Installer
Retaining walls are investments in both aesthetics and functionality, but they’re only as durable as the care and expertise that go into their construction. An experienced retaining wall contractor understands that every project requires thoughtful planning, precise engineering, and adherence to best practices in construction.
While smaller walls under four feet may not require an engineer’s plan, they still demand a professional’s touch when it comes to the essential elements like proper soil compaction, drainage, and footings. Each wall, regardless of height, benefits from being built to exacting standards—standards that only an experienced contractor can offer.
The Bottom Line: Expertise Matters
Building a retaining wall may seem straightforward, but it’s an engineered process that changes with each unique site. Hiring a skilled contractor like Landscape Jimmy the first time around ensures that your retaining wall is designed to withstand time and nature’s forces. Our team’s attention to detail, commitment to proper engineering, and focus on drainage solutions means that your wall will stand strong for years to come.
Don’t leave something as essential as structural integrity to chance. A well-built retaining wall enhances your property and provides peace of mind.
Reach out to us for a consultation, and let us show you how our expertise can turn your vision into a reliable, enduring reality.
