A well-made stone retaining wall is both functional, and beautiful to behold. Essentially, retaining walls are used to terrace slopes, to create more usable space, and simply to add form to an otherwise flat and featureless garden. Whatever the reason, to prevent issues with retaining walls, they must be well-built to remain solid, safe, functional and trouble-free. In fact, a good wall design starts behind the wall and below the ground. In other words, properly constructed drainage and foundations. So, read on to discover some of the critical elements required to avoid issues with retaining walls.
Common Issues with Retaining Walls
A well designed and built retaining wall should be a permanent feature. However, there can be problems with the construction, materials, or other environmental factors. Note: Before starting any wall construction, make sure you have council approval!
Pests – Wooden sleepers are pretty durable, lasting up to 20 years when treated. Nevertheless, termites, fungus and rot can undermine the stability of a wooden retaining wall.
Trees – Trees can threaten a retaining wall in several ways. For instance, if they are growing on the slope behind the wall, as they become larger, their additional weight can add pressure to the wall. Also, invasive root systems can crack or lift a wall, perhaps even making it collapse. In addition, tree roots can block or damage the drainage system. So, be sure to factor in the growth of any nearby trees.
Insufficient Drainage – Without sufficient drainage, such as gravel backfill and drainage pipes, your wall will suffer from too much water pressure. Look out for rising damp, mould or even water sitting at the top of the wall. So, if you think your drainage is blocked or was never fitted, try drilling weep holes into the wall to relieve the pressure.
Poor Soil Conditions – Some soil types are problematic and can create issues with retaining walls. For example, reactive clay expands considerably when wet and contracts when dry. This can destabilise your wall and create bowing and gaps. Consequently, your garden soil should be tested before construction to make your soil is suitable.
