Patios & paving · Practical advice
Why do patios sink and become uneven?
Discover why patios develop low spots or uneven slabs, with a focus on ground conditions, sub-base preparation, compaction and water beneath the paving.
Distinguish settlement from a loose slab
A patio can become uneven because supporting ground has settled, a bedding layer has failed or individual units have moved. A broad low area suggests a different investigation from one rocking corner. Mark the affected area on a simple sketch and note where rainwater collects.
Check whether the problem is recent, longstanding or worsening. Old trenches, an adjacent extension or changes to drainage can provide useful history. Include these details when requesting an inspection.
Investigate below the visible surface
Relaying slabs to a level line will not last if the material beneath them continues to move. A contractor may need to lift representative units and examine the bedding, sub-base and ground. The extent of that investigation should reflect the scale and pattern of the defect.
Edges and transitions also matter. A patio built partly over disturbed ground can behave differently across its width. A local patch should not simply bridge a weak area with extra bedding and leave the support unresolved.
Preserve a working drainage layout
The objective is not just an even-looking surface. Repaired levels must still direct rainfall appropriately and fit doors, steps and surrounding paths. Raising a sunken patch without considering the whole patio can move the puddle somewhere less convenient.
Discuss how any new levels relate to the building and drainage details. Where the original layout was unsuitable, the repair may need a broader redesign rather than a like-for-like reinstatement.
Choose between a local repair and reconstruction
If the defect is isolated and the surrounding construction is sound, lifting and relaying a defined area may be practical. Widespread settlement, failed support or multiple past repairs can make a larger reconstruction more sensible. Ask what observations support the recommendation.
Consider the availability of matching slabs and the risk of breakage during lifting. Reusing sound material can be worthwhile, but the quotation should allow for realistic losses. Keep records of the repaired layers and check the surface after rainfall once it returns to use.
Common questions
Can extra mortar under a slab solve a dip?
It may correct the visible height temporarily, but the supporting layers and drainage need assessing first. The right repair depends on why the dip formed.
Should a patio be perfectly level?
The surface should be even and usable, with a planned drainage fall where required. Evenness does not mean removing the slope needed to shed water.
Discuss your project
Tell us what you would like to change and share photographs of the area. We can discuss the next steps for your property.