Boulder rock walls are often used as a retaining wall to support soil in a sloping landscape.The rock wall structure needs to be securely constructed to withstand the weight of the soil lying behind it. Because boulder rock walls are exceptionally strong compared to other types of wall, they are a great choice when a strong retaining wall is required.
As well as natural strength, boulder rock walls also provide some lovely natural style to any landscape. Block walls do not always work when used in a more informal style of garden. They are also less effective as a retaining wall and generally more expensive to build due to the labour intensive nature of the construction. Some people use timber to act as a retaining wall for low level landscaping, but timber is also not the best material for long term use as it invariably rots over time, even when it has been treated with chemical preservatives.
Low level or small boulder rock walls can be constructed fairly easily. Once the area has been prepared, the rocks need to be carefully selected according to size. The largest rocks should be placed on the bottom of the wall and positioned so that they are touching one another. The second row of boulders needs to fit the contours of the rocks in the row below and each subsequent layer is treated in the same way.
For larger boulder rock wall projects, it is always best to use a specialist contractor to make sure your retaining wall is adequately constructed. When built correctly, a boulder rock wall will be even and symmetrical with no large gaps between the rocks. The large rocks will be in the lower rows and the top level of rocks should be level. Ideally the finished wall should look pleasing to the eye with no awkward anomalies and odd shaped rocks jutting out.
Boulder rock walls can be a great way to break up the different levels of a property that has been constructed on sloping land. They can also be an excellent method of landscaping the edge of driveways and patio areas. When built well, a boulder rock wall will be an enduring and very attractive feature of your landscaping. Over time, the rock wall will blend in and become part of the natural fabric of your garden as plants begin to grow over the rocks and natural mosses and lichens appear on the surface of the stones.