Garden walls have been used for centuries and can be an elegant, functional addition to your landscape design. Besides being aesthetically pleasing, a well-built retaining wall can prevent erosion, define elements of your landscape, and add to your home’s curb appeal. In this post, we’ll look at the types of walls used in landscaping and then give you some things to think about when choosing a wall.
First, let’s look at an example of what not to do when building a retaining wall to support a driveway. Can you spot what’s wrong?
That “uh-oh” moment
- The wall is made of wood, which is rotting and structurally unsound.
- Dirt is settling and pushing out the wall (see gaps at the base of the wall).
- Settling soil has also destabilized the asphalt that sits on top of it, thus the extensive cracking/crumbling.
- The asphalt isn’t thick enough to prevent grass from growing up through the driveway
The wall is supposed to be part of the foundation–the bedrock that supports the rest of the structure–but in this case the asphalt driveway is falling apart because the retaining wall is poorly constructed. A key takeaway here is you can avoid expensive mistakes by choosing the right contractor.
Things to know about walls: there are three main types.
1) Gravity Retaining Walls can be made of stone, concrete, or concrete blocks. They rely on their own weight to stand up without falling over and so are usually under 4 feet tall.
This is a stone gravity retaining wall made from 1-ton+ boulders.
Finally, we have concrete block walls. These walls are constructed from manufactured concrete wall blocks that can be placed in numerous ways. Though they may not add the same aesthetic feel as natural stone, they still have the same practical use and, with the right contractor, you can make them look great!
2) Reinforced Retaining Walls are usually 4-feet tall or higher, depending on city or state building codes. The additional height means this kind of wall requires more support than a gravity retaining wall. The best way to support these walls is with a product called geogrid.
3) Free-Standing Walls, like gravity retaining walls, rely on their weight to remain upright. Because they don’t have soil behind them, this kind of wall does not require additional support. Free-standing walls are often used as a division between properties, a beautiful alternative to a fence or hedgerow.
Knowing these basics will help you choose the right wall. When you sit down with your contractor, be sure to talk about these 5 things:
3) Existing Condition of Soil.
4) What will be above the wall (driveway, house, etc.).
5) Slope above the wall.