Settlement crack
A crack caused by the ground beneath the concrete moving downward unevenly, usually from poorly compacted fill, eroded soil, or a collapsed void.
What does settlement crack mean?
Settlement cracks are typically wider at one end, often accompanied by a vertical offset between the two sides, and they continue to move as long as the underlying cause remains. Unlike shrinkage cracks, they are a soil problem rather than a concrete problem, so patching without addressing the ground guarantees a return visit. Common triggers include trench backfill over utilities, downspouts discharging next to a slab, and fill placed without compaction.
In practice
A crack with one side sitting lower than the other is a settlement story, not a shrinkage story.