Frost heave occurs when ice forms underneath soil. As the frozen soil switches between freezing and thawing, it can cause the very foundation of your house to shift since frozen soil has about 10 percent more volume than dry soil. This can lead to serious structural damage to your foundation.
Frost heave can happen in any place that experiences cold temperatures. Yet it is most common when a source of water feeds into poorly drained or frost-susceptible soil like loams and silts. (In general, you can tell if you have these types of soils by touch. Loams are loose and will form a ball in your hand that crumbles when you poke it. Silts are made of small particles that feel slick and sticky when wet; they also resist water, so puddles will often form on top of them when it rains.)
Wall cracks are a telltale sign of frost heave. Cracks are most common on the interior walls, but they can also occur on exterior walls. Other signs of frost heave can include cracked, tilted or displaced concrete floor slabs.
If you notice any of these signs, you’ll want to get in touch with a foundation repair specialist. Some of the long-term steps they can take to help your house recover from frost heave after eliminating any contributing water sources include:
- Hydraway drainage systems: They direct water away from your foundation. In many ways, they are similar to French drains—but manufacturers often claim they are less prone to clogs than French drains.
- Helical piers: They act as shafts that bear the weight of your home.
- Helical wall anchors: They will permanently reinforce the foundation.
- Soil stabilization: This process involves injecting polymers into the soil so it will resist water infiltration.
- Soil replacement: This typically involves replacing poor soil with fill sand (a blend of sand, dirt and clay that compacts well) down to frost depth (this varies depending on where you live).
Heaving can also be caused by tree roots or pressure from nearby buildings. To find out what is causing damage to your house, make sure to contact a certified foundation contractor.
Contact your ERIE agent to make sure your home is protected along with everything inside (and outside) of it.
This story was originally published in 2014.