Problems
Concrete settlement
Something has moved and you want to understand whether it will keep moving.
Settlement is the ground beneath concrete losing volume, and the concrete following it down. It is the underlying process behind most sunken and uneven flatwork.
The reason it deserves its own page is that the fix depends much less on what the concrete looks like than on whether the settlement has finished. A slab lifted over finished settlement stays lifted. A slab lifted over ongoing settlement comes back down.
The usual mechanisms
Consolidation of fill: material placed during construction compresses under load over time. This is common where a slab sits over what was once a trench, a basement over-dig, or made-up ground, and it tends to be self-limiting — it finishes eventually.
Erosion: water moving through or under soil carries fine material away, leaving space behind. This does not finish on its own. It continues as long as the water keeps running the same way, which is why downspouts, grading and surface drainage matter so much.
Volume change in the soil itself: some soils shrink as they dry and swell as they wet, moving through cycles with the seasons and with nearby vegetation. This produces movement that comes and goes rather than progressing steadily.
Working out which one you have
Timing is the strongest clue available to a homeowner. Movement that appeared in the first few years after construction and then stopped points at consolidation. Movement that follows heavy rain, or that has continued steadily, points at water. Movement that seems worse in dry summers and eases afterwards points at soil volume change.
None of this is conclusive, and a contractor standing on the site with a probe will learn more in ten minutes than any amount of reasoning from a description. But arriving with a timeline makes the conversation better.
Why the cause changes the fix
Consolidation that has finished: lift it, and it should hold. Erosion: fix where the water goes first, then lift. Soil volume change: expect some ongoing seasonal movement and understand that any fix works within that.
A contractor who quotes a lift without asking about downspouts, grading or the history of the movement is quoting the concrete rather than the problem.
What to ask a contractor
- What do you think is causing this, and what did you look at to decide?
- Do you think this has finished, or is it ongoing?
- What needs to change about where water goes?
- If it settles again after you lift it, what does the warranty do?
Common questions
How long does settlement take to finish?
It varies enormously with the cause and the material, so any specific figure would be invented. Consolidation of construction fill is often described as taking years rather than decades. Erosion-driven settlement does not finish until the water is redirected. The practical answer is to measure your own: mark it, photograph it, and watch.
Does settlement mean my house is settling too?
Not usually. Exterior flatwork sits on shallow prepared ground; house foundations are built differently and to different depths. A settled driveway is common and rarely says anything about the structure. If you are seeing changes in the house itself — doors binding, cracks in walls, floors sloping — that is a separate question for a different professional.
Work it out, or judge the quote
Related guides
Sunken concrete
A slab that now sits lower than it should — almost always a ground problem, not a concrete problem.
Read more →Voids under concrete
Space beneath a slab — often before anything has visibly dropped.
Read more →Poor drainage around concrete
Where water goes decides how long concrete lasts — and it is the most commonly skipped part of a quote.
Read more →Concrete leveling
Raising settled slabs back toward their original height instead of tearing them out.
Read more →Leveling vs replacement
When lifting is the smart economy and when it is a deposit on a job you will still do.
Read more →