Why use an engineer?

Retaining walls, especially those over 1.2 meters in height or over 65º, are engineered structures exposed to enormous loading. Other than the fact that the council requires engineering diagrams for the plans to be passed, the walls need to be designed to withstand specific loads, all of which vary according to site.

One may not always realise it, but there are a number of factors which need to be taken into account when designing a retaining wall. These include:

• Internal friction angle of the soil on site.
• Sub-soil drainage requirements dependant on soil type, angle of the wall and wall height.
• Geo-fabric and shear keys for walls either over 65º or where unstable soil conditions are present.
• Friction co-efficient of the type of block being used.
• Depth, width and type of foundation required.
• Mass per square meter of the wall.
• Safety factors dependant on the site
• The distance of the wall from existing structures or structures still to be built.
• The liability involved if a wall does collapse.

The use of a qualified engineer ensures not only peace of mind but also provides a protection against liability in the case of a possible fault in the future.

Case In Point: Verwoed Rd, Lakeside