Timber Retaining Walls can be a really attractive form of soil retention. Machine rounded and pressure treated logs are placed in a trench, the trench is filled with a suitable quantity of concrete and the earth is rammed back, thus providing a solid wall. Ideal for uses where a bank of soil could deteriorate and dissipate if measures to retain it were not taken. A geotextile membrane is best used on the ‘retaining’ side to allow water through but to keep the soil back.
A very popular style of wall for use in schools or as a garden feature. However, due to the amount of work involved in the erection and the high level of materials, it is very expensive, but a very pleasing effect never-the-less.
Generally the timber that is used is machine rounded pressure treated softwood and is 100mm in diameter with chamfered tops, however 75mm, 125mm and 150mm diameter are all available.
Retaining wall are quite versatile, the logs can be erected to account for slopes and curves, or can be installed at different heights to look more interesting. The posts can be extended up to take rails and pales to form a timber palisade fence above the wall.
Timber retaining wall construction
Effective for raised beds