3 Key Points to Know about Soil Thermal Resistivity Testing

If you are a subdivision contractor and developer, you may know about soil thermal resistivity testing. You may know that this process needs to happen in order for cabling to be placed underground throughout the subdivision. What you may not know is what the process entails and what each step may mean for your subdivision plans. Here are three main points you should know about the soil thermal resistivity testing.

Sample Collection

The first step to the soil thermal resistivity testing is to take soil samples. These samples are taken from the depth the cables or thermal units will be placed. This does mean that several holes may be placed throughout the area to extract the soil samples. The reason for this is to determine if soil is suitable throughout the area and not just in one or two spots. The soil resistivity can change due to different environmental factors or previous issues such as contamination.

Moisture Content Testing

Once the soil samples are collected, the soil will be taken to a lab for further testing. In general the testing consists of drying out the soil and separating it. The soil is then tested for thermal resistance at different moisture levels. This will let the lab know if the soil is only resistant to a certain moisture point and what options may be available to either avoid the area the soil is located or to help the soil become more thermal resistant. This step of the process may take several days to weeks depending on the amount of soil and testing that needs to be done per the request of the contractor or area guidelines for testing of this kind.

Results and Consultation

There is a misconception that if the soil is not suitable the area can not be used for underground cable or thermal conductors. The truth is, if the soil is not suitable, a consultation can happen with the lab company. This consultation will be held to discuss other options for that soil. One of the options may be to bring in backfill soil to help with the resistance to the soil that is present. Other options may be discussed for budgeting reasons or due to the scope of the specific construction project.

If you are concerned about the soil in the area, and if it is possible, have the testing done as part of the preliminary planning process. This will help you maintain the schedule for subdivision planning and keep you on track. If you have questions regarding the process, consider a consultation with the testing division contractors.