Heave is NOT settlement - but it does show similar signs. AquaGuard's sales representatives are well-educated to distinguish between the signs of heave verses settlement.
What is foundation heave? Heave is the upward movement of a foundation or slab caused by expanding or swelling of the clay soils due to an increase in moisture. Although heave can been seen in foundations, it is often a problem for slabs because the weight of your home on the foundation is fully in effect. Heave is usually displayed in the first few years after the home's construction, unless there are long periods of drought.
What causes heave? When a hole is dug for a new home, the upper soil layers are often dry- or, the hole in the soil is left open, which causes the soil to dry out. After a home is built, the moisture contents of dry soils below interior slabs will increase. As these moisture levels increase, the clay soil expands which causes pressure on the floor slab. The floor slab tries to accommodate this swelling by pushing upward causing cracks.
What are the tell-tale signs of foundation heave? To homeowners, the problems caused by heave may appear like the exterior walls are moving downward, rather than upward. Unlike foundation settlement, you will not see any cracking on the outside foundation walls; instead, the cracking will be seen in the interior partition walls and floors. Also, multiple heave cracks come together to a point to form an enclosed loop where the heave is the greatest.