This foam will never lose density or shrink. This material is lighter than traditional mud-jacking material, and as a result, puts less stress on the unstable soils beneath your concrete. Unstable soils are the reason that your concrete has settled. Level Up concrete lifting foams infiltrate the air spaces within the underlying soils and aggregates beneath your concrete, and essentially bind them together so that the foam has a stable surface to lift against. This material is non-erodible and non-decomposable due to its hydrophobic properties.