Note, however, that most jurisdictions require permits and engineering drawings for all retaining walls over 3 to 4 feet in height, especially if the soil behind them supports a surcharge (a load ...

For instance, a study demonstrated that various densities and thicknesses of EPS geofoam effectively minimized lateral earth pressure on rigid retaining walls subjected to surcharge loading ...

Some local codes may also demand permits for retaining walls that support a vertical load on top of the soil behind them ...