It is important to determine the stability and therefore safety of any retaining wall on a property. An unstable retaining wall may collapse and cause damage to other structures around the wall or injure or even kill a person standing nearby.
Any retaining walls over one meter high and in close proximity to an adjoining dwelling requires footings to be designed by a structural or civil engineer.
When inspecting any retaining walls:

If you notice any of the above conditions in a retaining wall that is over one meter in height contact a structural engineer for further advice. If the retaining wall is less than one meter high contact a licensed builder or landscaper.
Just remember that the condition of the retaining wall is only one of the numerous areas of a house that needs to be checked before buying or selling – the easiest way to do this is by purchasing the Residential Building Report Guide.
