Get matched with top retaining wall installation pros in Marion, SC

Yes, to build a retaining wall, a permit is required. Similarly, any repairs or modifications to an existing retaining wall require permits. If the planned wall measures higher than 4 feet, most municipalities require designs and permits come through a licensed engineer. In some locations, if the wall is shorter than 4 feet, a permit may not be required. For the requirements in your area, contact your local government.

Poured concrete is often the cheapest material for a retaining wall, costing around $6 to $8 per square foot. Other budget-friendly options include vinyl and landscaping timbers, which range from $10 to $15 per square foot; landscaping timbers are particularly well-suited for DIY projects. Untreated timber and railroad ties are a step up in price, starting at $15 to $25 per square foot. Natural stones can also be a cost-effective choice if you can source them from your own property, but they can be expensive to purchase. High-end materials like steel are typically the most expensive but offer superior durability and aesthetics.

The lifespan of a retaining wall varies based on its material, installation quality, maintenance, and local climate, with an average range of 20 to 100 years. Retaining walls made from durable materials like concrete, stone, and brick generally last a minimum of 50 years. Concrete walls typically last between 50 and 100 years, while brick can last for over a century in ideal conditions. Timber retaining walls can last from 20 to 40 years, depending on the wood quality, and pressure-treated wood walls average around 30 years. It is important to note that a retaining wall can fail prematurely if it was poorly constructed, for example, with inefficient footings or without necessary rebar reinforcements.

Most railroad tie retaining walls have a life span of 20 to 30 years, though you may need to replace your wall sooner if it’s repeatedly exposed to heavy rain, runoff, and excess moisture. Railroad ties are typically treated with creosote, which makes them much more durable than untreated wood. Though they last longer, they don’t last forever. For the most longevity, make sure your retaining wall has a sturdy base and steel reinforcements. You should also install drainage to direct water away from the wall.