What Is Foundation Settlement?
You may be experiencing unlevel or sloped floors, cracks in your walls or doors sticking. These can all be signs of foundation settling. You are not alone as foundation settlement is a common problem in California
It’s very common for a foundation to settle into the soil slightly after it’s built. This is usually no cause for concern so long as the settlement is uniform. The problems start when the settlement is differential. With differential settlement the foundation is settling into the soil unevenly… Causing some unsightly things to happen around the home such as door sticking, windows not closing, sloping floors, and cracks. See the infographic below for more information:
Foundation settlement can be very frustrating, especially with the expansive soils found all around the Bay Area, as the active soils change with the seasons, heaving in the winter as the soil retains the water and then retracting in the summer as that water evaporates. Most residential foundations are constructed with shallow foundations leaving the home very susceptible to this ground movement.
What Causes Foundation Settlement?
- Soil that wasn’t adequately tamped down before construction - Soil needs to be compacted before anything gets built on top of it. If this isn’t done properly, the structure will settle into the ground after construction and this could lead to differential foundation settlement.
- Expansive soil - Expansive soil has a lot of clay in it and because of this it will swell as it soaks up water and then shrink as it dries out. Over time, this swelling-shrinking cycle creates movement under the foundation and can result in differential settlement.
- Natural disasters such as earthquakes and floods
- Improper Drainage - Having downspouts properly installed can be another reason your home is experiencing settlement. Leading the water away from the home’s foundation can be crucial.
- Excavation too close to the foundation - If your neighbor starts excavating, it could destabilize the soil under your home’s foundation leading to settlement.
- Weather changes - An example of this would be building a home on top of expansive soil during the dry season, and then when the rainy season comes around again, the soil swells creating movement under the foundation that could lead to differential settlement.
For more information see, Foundation Settlement.
Signs of Foundation Settlement
How to Resolve Foundation Settlement
A deep foundation system such as resistance piers/push piers, helical piers or concrete drilled piers are in most cases the best way to provide you a permanent solution to foundation settlement. They work by installing piers along your existing foundation extending down to bedrock or load bearing strata, ensuring your home’s foundation is supported on stable material.