So, what is a sitting wall? A sitting wall is a low wall built on a patio that can also serve as seating. Typically built to the vertical height of approximately 18" to 21", a sitting wall is usually about 12" to 24" wide. This allows an individual to sit in a comfortable position.
There are many reasons why a retaining wall can fall over. In our industry most, if not all, manufacturers of interlocking block have cross-section sheets on how tall of a wall you can build with their block - in good soils (gravels and sands) and with level compacted backfill. Many times installers will exceed those recommended heights, or there ends up being a slope above the retaining walls which adds a significant amount of extra pressure. If this is the case you have three options:
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