Soil consolidation is the gradual compression of soil under sustained load as water and air are slowly squeezed out, a natural process that causes even well-built slabs to settle over time.
In depth
Unlike sudden washout, consolidation is slow and quiet. Fill soil around new construction is the classic case. Even when compacted at build time, deeper layers keep consolidating for years, which is why driveways and sidewalks in newer subdivisions so often develop settlement in years 3 through 10.
Consolidation rarely happens evenly. One corner of a garage approach sits over deeper fill than another, consolidates more, and the slab tips, creating the classic cracked, uneven look of differential settlement.
How Acme applies it. We fill the voids consolidation leaves behind and lift the slab back to grade with polyurethane. Because the foam is lightweight, it does not restart the consolidation cycle the way pumping in heavy slurry can.
Related terms: Concrete Settlement, Differential Settlement, Soil Compaction, Subgrade
Frequently asked questions
How is consolidation different from washout?
Washout physically removes soil with moving water. Consolidation compresses the soil that is still there. Both leave the slab unsupported, and both are fixable with foam.
My house is 8 years old. Why is the driveway just now sinking?
That timing is typical. Deep fill placed during construction can take years to finish consolidating, and the slab settles right along with it.