How to Build a Retaining Wall How to Build a Retaining Wall
The simple practise of building retaining walls has been around for thousands of years and is used to retain level surfaces in sloping areas and hold back soil. They can also be used to enclose an area for decorative purposes in your garden and can be filled with plants, coloured chippings, or perhaps an artistic design.
The type of wall you require will depend very much on the required height of the wall, the slope of the ground above the wall, the type of soil and the weight applied on the soil above the ground - from trucks, cars, etc. The addition of a retaining wall alters the balance of a hillside, and the higher the wall is, the more force there is behind it, which could potentially cause it to slide or slip over. So, it is definitely not advisable to attempt to erect walls yourself over 4 feet high without first seeking advice from a structural or civil engineer.
Segmental retaining walls offer the best possibilities for the DIY enthusiast, as they are relatively easy to erect and require a minimal amount of tools. They come in decorative concrete, or plain concrete blocks, which can be stacked and interlocked with one another and do not require the use of mortar. These blocks generally rest on a level bed of sand, avoiding the addition of any thick concrete footings and can therefore be laid at any time of the year as long as the ground is not frozen underneath. You can create steps and flat areas to assist in climbing up a hillside, curves or just plain straight walls using this method. This idea also gives you the option of moving your walls if you change your mind. You can simply take them up and start building them somewhere else.
Another important point that needs to be considered when constructing a retaining wall is drainage. This is a crucial factor, as any water held in the soil will put additional strain on the wall. The mortarless system, however, does at least offer its own built-in drainage system, as water can usually seep perfectly through the cracks between the blocks.
Once you have measured out the area - remember that you will need to grade it on the downhill side of the wall - it is a good idea to mark out the area with stakes and string. This will help to guide you as you dig out your trench - for a curved wall you can use a hosepipe to gain the required shape. Your trench will need to be around 4 inches deep and the same width of your blocks, then filled with one to two inches of sand, which must be compacted down. As you begin to lay the blocks, you will need to continually check their level as you go along and tap them in with a hammer, if necessary.
You will have to make suitable adjustments for sloping areas, which may require a sequence of steps. Once you have completed the ground level blocks, you can begin interlocking the next level above.
There are countless ideas and color patterns that can be used to create a perfect wall. It is probably a good idea to have a look around at other gardens, or garden center designs to decide what you think would suit your garden and individual tastes. Whatever you choose, it is important to make sure you seek the right advice and purchase the correct materials before you start. This will help to ensure that your walls stay looking good for many years to come.