In all truth, the causes of settlement are not always obvious, because all settlement happens below ground. We can’t actually see what’s happening underground right?
The best practice, is to simply assume that whatever happened, it was caused by inadequate soils under the footing. The only way a footing can be allowed to sink is because the soils under the footing are failing to support the foundation.
So…. Bypassing problem soils should be the goal, not just addressing the causes of settlement.
These are the most common causes of foundation settlement in VA:
Tree Root Decomposition
After cutting down large trees near the foundation, the tree roots can decompose, rot away, and open voids under the foundation.
Standing Water Along The Home
If standing water is held against the foundation, it can cause various problems increasing your chances for foundation settlement.
Underground Water Runoff
Running water under the foundation can slowly erode the soil under your footing over time and open large voids, leading to settlement.
Weak Compressible Soils (Clays, Silts, Peats)
Not all ground is meant to be built on. Weak soil types can sink under the weight of a home causing settlement.
Voids open up under the top layer of soil as underground water washes out the soil and creates openings below the surface. If the ground is collapsing under your foundation, it’s important to support the home on the strong soils underneath the affected soils with foundation push piers.
Insufficient Compaction under the Footing
If the supporting soils under the footing aren’t strong, they can sink under the weight of the home.
Moles Digging Holes
As moles dig tunnels around the yard, they soften the soils. If the soils under your foundation are softened and dug out, it can increase the chances for foundation cracks.
Shrink Swell Soils (Clays)
Clay soils can shrink with long period of dryness and swell with an abundance of moisture. As clay shrinks due to dryness, it can open voids large enough to allow settlement.