• That’s not structural damage. The wall and the pavement were made separately, there will always be a gap between them. Judging by the rough edge it probably used to look like there was no gap? Someone just decided to make the wall render butt up against the ground, but that only sometimes hides the gap.

    The gap will change size over the years due to expansion and contraction (caused by heating, cooling & moisture) and ground movement (including settling).