Some are harmless. Others are the first clear sign that your property is starting to move. Once movement starts it rarely stops on its own — which is why getting an engineer involved early can save you serious money and prevent long-term damage.

At Subsidence Ltd we give advice and do the remedial work every day. We stabilise homes across the UK using resin injection that supports foundations with precision. We are usually in and out in a single day, and you do not need to move out or empty your home.

In masonry walls, the most diagnostic feature is whether the crack steps through the mortar joints (typical of subsidence) or runs straight through the bricks themselves (more typical of severe settlement or overload).

A diagonal stepped crack rising from the corner of a window opening, widening toward the top of the wall, is the strongest single visual indicator of foundation movement.

In rendered walls, look for the underlying pattern. A crack that follows a stepped line beneath flat render is usually masonry movement, not the render itself. A crack with sharp, straight edges only on the surface is more likely a render failure.

Internal plaster cracks above doors and windows are usually lintel deflection, not subsidence — unless they’re accompanied by external diagonal cracking.