The property managers of this mid 90’s Tempe warehouse building reached out to us after symptoms of a potential foundation problem were discovered.
- Interior & Exterior Wall Cracks
- Floor Cracks
- Floors out of Level
A complete foundation inspection concluded the commercial property to be experiencing both foundation settlement and foundation heave.
Addressing foundation settlement often requires foundation underpinning. Addressing heave can be a bit trickier. This case study will focus on addressing foundation heave via sub slab depressureization.
This phenomenon usually occurs in areas where structures are built on expansive clays. Moisture from one or any combination of sources – including: storm runoff, poor drainage around the foundation, plumbing leaks and underground moisture sources - will allow the moisture to accumulate underneath the foundation. This moisture then interacts with the clay soils, causing them to swell or heave. The clay soils take the path of least resistance and expand upwards, lifting the foundation. The area where the heave is located needs to be dealt with by eliminating the sources of moisture and addressing the existing moisture. This should stop the heave pattern from rising further and in some areas allow the existing heave to subside.
We believe that the proper way to deal with foundation heave pattern is by lowering and managing the moisture content of expansive clays that cause heaving. It is our recommendation to manage the moisture underneath the foundation through active soil depressurization. This process will remove existing moisture from the soil as well as prevent new moisture from the expanding the clay further by bringing the moisture content down to an optimal level using both convection and evaporation. This will mitigate future heaving of the clay soil and possibly allow existing heaving to subside. This process can take six months to several years to reach equilibrium.
The MoistureLevel Smart Foundation System is designed to control the moisture of expansive clays that cause heaving under the building. If optimal results are not achieved with the MoistureLevel Smart Foundation System, more aggressive measures may be required. The manometer and foundation survey will act as a baseline to measure performance over time should additional foundation services be required.
The MoistureLevel Smart Foundation System also comes complete with a warranty – commercial or residential.