Retaining walls can be constructed from a range of materials including timber, stone and concrete. Material suppliers will typically stock a selection of these, along with accessories such as support posts and mortar.

The following are the most widely utilised materials:

Timber -- any number of species with sleepers and treated pine popular options. Timber has the advantage that it drains easily, though it needs to be treated for durability against insects and moisture

Stone -- granite, sandstone and limestone amongst others. Natural stone is attractive to look at and extremely durable but does come at a cost premium

Concrete -- pre-cast slabs, sleepers and masonry blocks. Concrete is relatively inexpensive and extremely durable, with the advantage it can be manufactured in a number of different configurations and styles.

An important factor when constructing any retaining wall is the installation of adequate drainage. This is to prevent the build up water on the retaining wall, which can cause timber to rot, and may lead to the collapse of any wall.

If you are planning a retaining wall on your property, consider the following prior to construction:

• adequate drainage must be specified
• determine the soil type on your property
• walls above a certain height will require building approval, so check with your council
• Australian Standard AS 4678 details construction requirements for earth-retaining structures