Concrete cracking is the fracturing of a slab, which frequently signals lost or uneven support from settlement, under-slab voids, or soil movement, though it can also result from shrinkage or surface conditions.
In depth
Not all cracks mean the same thing, but cracks that widen, step, or run with a drop in the slab usually point to a support problem: the soil beneath has settled or washed out, leaving the concrete to span an unsupported space until it fractures. Water then penetrates the crack and erodes the base further, accelerating both the crack and the sinking.
Where cracking is driven by lost support, raising and void filling address the cause by restoring soil contact. Cracks from surface shrinkage or curing are cosmetic and handled differently.
How Acme applies it. Acme notes that water penetrating through surface cracks slowly erodes the base material, weakening it and causing the concrete to sink and crack further over time, so filling voids and managing water are key.
Related terms: Concrete Settlement, Under-Slab Void, Differential Settlement, Frost Heave
Frequently asked questions
Do cracks mean my concrete is sinking?
Not always, but cracks that accompany a drop in the slab, widen over time, or step at a joint often indicate the soil beneath has settled or a void has formed.
Can raising concrete stop cracks from spreading?
When cracking is caused by lost support, filling the void and restoring soil contact removes the stress causing it, though existing cracks may still need sealing to keep water out.