Why is doing a soils analysis so important?  Why employ a Geotech at all? The importance of this work simply can’t be overstated. Not only is soils analysis a critical component of a pre-build site investigation, but it is also a legal requirement to acquire a building permit in most jurisdictions.

But what is so important about the soil onsite? Understanding soil composition can play a huge role in what measures must be taken to ensure that a structure is safe and constructed in the most stable way possible, while optimizing costs.

Along with understanding soil composition, a geotechnical engineer will take the findings of a soil investigation to formulate a unique risk-mitigation plan for your build site. Still wondering why you need to have a Geotech onsite before building? Continue reading with us below and allow our experience and expertise to guide your project.


Why Do You Need a Geotech Onsite Before Building?

Why is soils analysis so important in construction? While you may be able to build with the strongest materials and the most innovative techniques, a lack of duly paid consideration to the foundation of your project could very well lead to an inevitable disaster. A simple answer to why you do geotechnical exploration and investigation is to avoid risks and hazardous conditions. Let’s take a closer look at what the potential hazards that must be planned for below.

What Do Soil Investigations Look For?

Simply put, soil investigations are looking to determine the suitability of soil for a proposed construction project. The soil beneath a structure is responsible for absorbing the stressors that come from a building, so understanding how a particular soil will react is critical. Failing to properly test and analyze the soil could lead to a structure that crumbles, settles, or decays well before its time.

Testing is done by experienced geotechnical engineers who are trained to take proper samples. Boreholes are drilled in various locations across a property and samples are then taken to a soils lab for testing.

So, what types of tests are conducted? The following tests are often used to determine the qualities of soil at a job site:

  • Moisture content test (tells a lot about the in-place soil conditions)
  • Atterberg limits tests (helps to classify fine-grained soils like silts and clays)
  • Dry density of soil (helps to determine “weight” of soil and how it relates to many factors related to construction)
  • Shear strength and “phi” angle  (soil parameters that correlate to other building relationships)
  • Compression tests  (how much pressure the soil can handle before failure, and how it fails)
  • Proctor compaction test (done to help determine optimal moisture and density for construction compaction testing)

What Hazards Can Soil Tests Detect?

A wide range of risks and hazards can be detected and avoided through proper soil testing. Cutting corners during soil analysis will almost always lead to unforeseen costs and delays in the construction process. If problems are uncovered during the build process, mitigation planning and building techniques must be implemented on the fly. Sometimes these measures don’t mesh well with current plans. In other cases, uncertainty can lead to costly over-engineering where foundations are concerned. It’s far easier and more budget-friendly to determine hazards before construction begins, and then develop a plan to design accordingly.

Along with delays and added costs, there are other risks that can arise when proper soil testing is ignored. A full geotechnical investigation helps geotechnical engineers understand how soil will react to compaction, water saturation, seismic activity, permafrost, and more. This information is then passed on to the rest of the design team (especially structural engineers) to help all other aspects of the project design.  Understanding the way soil reacts to a variety of conditions will offer a chance to craft an effective plan to mitigate risks.

Geotechnical investigations are best completed during pre-construction planning, sometimes even before the purchase of a property. This can go a long way towards determining if your future build plans are feasible at your proposed site.

However, time must also be given during construction to conduct soil evaluations after the heavy equipment has dug out the foundation. While soil testing can continue at various stages, it is vital — and often legally required — that an investigation is done before building in order to ensure that a project is safe and adequately designed.


Turn to Central Geotechnical Services for Guidance

Looking for personalized answers to the question, “Why do you need a Geotech onsite before building?” If you need guidance on your next project, our team offers a host of services to help you pull off a successful build. Here at Central Geotech, we’ve seen it all in our work, and would love to help you with your next job.

We can offer insight into why you do a soil test, how to interpret your soil analysis, and can provide planning assistance to craft a safe structure based on the conditions at your site. Get in touch with us for a consultation, or explore our educational resources to learn more today!