A retaining wall is just like any other construction project, except on a smaller scale. And like any other construction project, there are three main costs: Materials, labor and miscellaneous items.

Materials: The customer has the most control during material selection. While having a beautifully finished wall is of paramount importance, it?s important to weigh function equally with form. For example, using wood for a retaining wall may not be the best choice if extreme moisture is a factor as termites and wood rot may sharply decrease the lifespan of the wall. A good contractor can help choose the material with the best combination of looks and functionality, ensuring an aesthetically pleasing final product that lasts for years.

Labor: Several different factors can drive up labor costs quickly. A wall of greater-than-average height can increase costs, and how easily the workers can access the project site will also impact the final labor quote. If a gate or fence has to be taken apart or removed in order to bring materials to the site and perform the work, count on adding this time to the overall labor cost. In addition, labor may also be added if the dirt removed has to be disposed of somewhere other than the project property. Figure an average labor cost of $53 to $58 an hour, depending on your region.

Miscellaneous costs: These costs include specific tools needed to perform certain work during construction or even additional materials to strengthen the wall itself. For example, soils with heavy clay content retain water much more than those low in clay. This extra water weight requires that some retaining walls be constructed with additional materials, usually fabrics, that distribute the weight evenly over the wall to prevent failure. Reasonable miscellaneous costs run in the range of about a dollar per square foot.

Pitfalls of Retaining Walls

Building a long-lasting retaining wall is vastly more complicated than simply piling up blocks and shoveling dirt. Moisture is the primary enemy of retaining walls, and if not properly mitigated, can lead to costly failures. Cracks are also a common feature in concrete walls that haven't been properly drained, due to the extra weight and temperature differences that come with moisture-soaked soils.

If the wall is going to be higher than average, professional help may be required. Some states require the use of an engineer during the design process if the retaining wall exceeds a specific number of vertical feet. The overall height includes the portion that is buried in the dirt, known as the "key", which is vital to ensure the lower portion of the wall doesn't collapse and cause soil sliding. Be sure to check local building codes regarding retaining wall height; if the intended wall requires using an engineer, count on the overall cost going up quickly.

Luckily, most retaining wall projects don't have every single factor that increases cost present. On average, most only have two or three common factors which most contractors can easily work with.

Plan Well for Best Results

Retaining walls can be beautiful and capable, and if done well, will last for several decades. However, with so many factors at play during design and construction that can lead to a poor outcome, take the time necessary to decide what size of wall will best suit the need as well as which acceptable materials will last the longest. Using professional contractors and engineers as needed will ensure the perfect end result and years of reliable use from the retaining wall.