Site Plans & Engineering
Geotechnical Investigations & Soil Testing
Geotechnical investigations, soil borings, soil testing and compaction testing by licensed engineering firms – assessed first, then scoped and priced.
Overview
The ground under a building matters as much as the building itself. A geotechnical investigation tells the structural and civil engineers what the soil is made of, how much load it can carry, where the water table sits, and whether conditions such as organic material, loose sand or voids need to be addressed before foundations are designed.
Investigations, testing and reports are performed by licensed geotechnical engineering firms and testing laboratories. We define what the project needs with the design team, coordinate site access and the drilling or testing equipment, and make sure the findings reach the engineers who design the foundation and site work.
Because results are not known until the testing is done, this is assessment-based work: the scope and cost of any foundation or site measures depend on what the investigation finds.
Who it’s for
- New homes and buildings where the structural engineer needs soil data for foundation design
- Additions on soils that may differ from those under the existing structure
- Sites with fill, organic soils or a high water table
- Commercial projects where geotechnical reports are required for permitting
- Construction requiring compaction testing of fill and building pads
What’s included
Typically included
- Scoping the investigation with the structural and civil engineers
- Coordinating soil borings or cone penetration tests at locations the engineer specifies
- Laboratory soil testing for classification, moisture and organic content as specified
- A sealed geotechnical report with findings and foundation recommendations
- Distribution of the report to the design team and review of how it affects foundation and site design
- Compaction testing of fill, building pads and utility trench backfill during construction
- Density and testing records kept for inspections and closeout
Common exclusions
- Foundation, ground improvement or remediation work recommended by the report, scoped and priced once findings are known
- Sinkhole investigations, which follow their own assessment process
- Environmental site assessments and contamination testing
- Site clearing or access work needed for drilling equipment, priced separately if required
Every proposal lists its own inclusions and exclusions in writing.
Materials, design options & upgrades
How pricing works
Geotechnical work is assessment-based. The investigation itself is priced from the engineer’s proposal, based on the number and depth of borings or soundings and the laboratory tests specified. What the investigation finds then determines the foundation and site preparation scope, which cannot be priced accurately until the report is complete.
Compaction and materials testing during construction is priced from the number of tests and site visits the specifications call for.
What changes the cost
- Number, type and depth of borings or soundings
- Laboratory tests specified by the engineer
- Site access for drilling equipment
- Whether initial results require supplemental investigation
- Number of compaction and materials tests during construction
- Recommendations in the report, such as removal of unsuitable soil or ground improvement
If this work is part of a larger project, it’s priced within that project’s budget — please don’t add separate estimates together. Read the pricing guide.
Typical stages
Scope
The structural and civil engineers specify what information they need; the geotechnical firm proposes the investigation.
Field investigation
Borings or soundings are performed at specified locations, and samples are collected.
Laboratory testing
Samples are tested and classified as the engineer requires.
Report
The geotechnical engineer issues a sealed report with findings and recommendations.
Design and pricing
Foundation and site designs are finalized from the report, and the resulting work is scoped and priced.
Construction testing
Fill and pads are compaction-tested as they are placed, with records kept for inspections.
What affects the schedule
- Testing firm and drilling equipment availability
- Site access, clearing and utility locates before drilling
- Laboratory turnaround for specified tests
- Results that call for supplemental investigation
- Coordination of compaction tests with the earthwork sequence
Questions & answers
Why do I need soil testing?
The foundation design depends on what the soil can support. Testing gives the engineer real data instead of assumptions, which can avoid both under-designed foundations and unnecessary cost.
What if the report finds poor soil?
The engineer’s recommendations may include removing and replacing unsuitable material, ground improvement, or a different foundation type. We scope and price that work once the recommendations are known.
Is a geotechnical investigation the same as a sinkhole investigation?
No. A sinkhole investigation follows its own assessment process and testing methods. If sinkhole activity is a concern, we coordinate that assessment separately.
Start here
Planning geotechnical investigations & soil testing?
A short form — three steps, a few minutes. Share plans or photos if you have them. We’ll review it and follow up using the contact details you provide.