Avoiding Retaining Wall Failures

Retaining walls can transform hilly areas into usable level spaces, protect roads and property from falling rocks and soil, and prevent erosion. When they fail, they can cause considerable damage and potential legal action from neighboring properties. 

To prevent this from happening, retaining walls need a solid residential landscape design and must be built with the right materials and construction techniques. 

Signs of a Failing Retaining Wall

Building a wall that can hold back huge amounts of earth is not easy. One of the best ways to avoid retaining wall failures is by learning to recognize them. Be sure to regularly inspect the wall and watch for signs of a problem, or you could face costly repairs.

Here are some common warning signs of a possible retaining wall failure:

• Leaning: The wall is tilting forward as though it might fall.

• Bulging: A curve or bump appears in the face of the wall.

• Cracking: Horizontal or stair-step lines appear.

• Gaps and separations: Openings appear between the blocks or where the wall abuts buildings or other structures.

• Water buildup and seepage: Water starts pooling behind or around the wall or seeping through joints.

• Erosion: Soil that provides structural support begins to wash away.

You can repair or replace failing retaining walls, but it is far less disruptive and expensive to build the wall right the first time. 

Tips for Avoiding Retaining Wall Failures

Sometimes, unforeseen circumstances compromise a retaining wall's integrity. Maybe the upper area is subjected to unexpected weight, like a parked car, or the soil under the retaining wall becomes unstable.

Outside of these surprises, structural problems can almost always be avoided by studying the site and developing a plan that addresses potential issues.

Design Specifically for Each Location

A landscape designer needs to evaluate the conditions of the proposed site and consider how those conditions will change with the seasons. For example, if the soil is too soft or expands and contracts too much with temperature changes, it may not support a tall or heavy wall. 

Install Enough Drainage

Poor drainage is the leading cause of retaining wall failures. When soil is saturated, it weighs 50% more than dry soil, which can place tremendous pressure on a retaining wall. A retaining wall needs enough drainage to handle heavy rain and wet conditions.

When gravel is used in drainage systems, water flows through the stone and away from the wall. Weep holes (small openings placed near the base of a wall) and perforated pipes also help trapped water escape. Backfill is the material placed behind the wall. 

Three-quarter-inch crushed stone can help prevent trapped water from building up behind a wall and provide stability when compacted properly. 

Don’t Cut Corners on Materials or Installation

Retaining walls built using cheap materials, without a strong foundation or proper compaction, or out of alignment are more likely to fail. If you’re wondering whether hiring a landscaper is worth it, working with experienced landscape designers and contractors who follow industry best practices and use quality building materials (not just aesthetically pleasing ones) can be one of the best ways to avoid retaining wall problems.

Experience Counts When Installing a Retaining Wall

When retaining walls fail, they’re more than just an eyesore. They can cause massive damage to nearby structures, yards, vehicles, and landscaping. 

Michaelangelo’s Sustainable Landscape and Design Group understands what it takes to design and build landscapes that will stand the test of time. We also know how to use the best landscape lighting for ambiance and security so that your retaining wall is both safe and beautiful.

As one client in Marietta said, “Michaelangelo's provided excellent quality and professionalism. They designed and constructed our entire backyard with retaining walls, hardscaping, landscaping, firepit, lighting, irrigation, and pathways. The design and execution exceeded our expectations! They finished within budget, on time, and [provided] excellent quality.”

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