Geotechnical Site Investigation
Professional desk studies, ground investigations, laboratory testing and geotechnical reporting for residential, commercial and mixed-use developments throughout the UK.
Understand the Ground Before You Build
A geotechnical site investigation helps establish the ground conditions beneath a proposed development. It can identify potential issues relating to soil strength, made ground, groundwater, shrinkable clay, contamination, mining activity, unstable ground and foundation design.
One Stop Consult coordinates experienced geotechnical and environmental specialists to deliver the appropriate level of investigation for your project, from an initial Phase 1 Desk Study through to intrusive site works, laboratory testing and detailed reporting.
Early investigation helps the design team make informed decisions, reduce uncertainty and avoid costly surprises once construction begins.
Ground Investigation Services for Development Projects
The investigation scope is tailored to the proposed development, site history, geology and regulatory requirements.
Phase 1 Desk Study
Review of historical mapping, geology, environmental records, mining information and previous land uses to identify potential ground and contamination risks.
Site Walkover Survey
A visual inspection of the site and surrounding area to record current conditions, potential hazards, access constraints and evidence of previous development or contamination.
Phase 2 Site Investigation
Intrusive investigation using methods such as trial pits, window sampling, boreholes or dynamic probing to assess ground conditions beneath the site.
Laboratory Testing
Geotechnical and chemical testing of soil, made ground and groundwater samples to support foundation, contamination and earthworks recommendations.
Foundation Recommendations
Practical recommendations relating to foundation type, founding depth, allowable bearing pressure, ground improvement and other construction considerations.
Remediation and Validation
Remediation strategy support, verification testing and validation reporting where unacceptable contamination or other ground risks are identified.
Phase 1 and Phase 2 Investigations
A Phase 1 Desk Study is a non-intrusive assessment based on available records, mapping and a site walkover. It develops an initial understanding of the site's environmental and geotechnical setting.
Where the desk study identifies potential risks or where detailed design information is required, a Phase 2 intrusive investigation can then be prepared to test the actual conditions beneath the site.
What Can a Site Investigation Identify?
The investigation provides information that can influence design, planning, cost and construction methodology.
Made Ground
Variable or uncontrolled fill can affect bearing capacity, settlement, excavation and foundation design.
Contaminated Land
Previous industrial or commercial use may have affected soil, groundwater or ground gas conditions.
Shrinkable Clay
Clay soils and nearby vegetation can influence foundation depth and the risk of ground movement.
Groundwater
Groundwater can affect excavation stability, drainage, waterproofing and construction methodology.
Mining and Voids
Historical mining, quarrying, shafts or natural cavities may require further investigation or specialist treatment.
Weak or Unstable Ground
Soft deposits, loose soils, peat or slope instability may require alternative foundations or ground improvement.
Investigation Methods
The chosen methods depend on the scale of the project, expected geology, site access, proposed foundations and the risks identified during the desk study.
Project Review
Review the site address, development proposal, available drawings and regulatory requirements.
Desk Study
Assess historical land use, geology, environmental records and potential ground risks.
Intrusive Investigation
Complete the agreed site works using appropriate investigation and sampling methods.
Testing and Assessment
Analyse samples and assess the results against the proposed development and identified risks.
Report and Recommendations
Issue a clear report setting out findings, recommendations and any further actions required.
What the Geotechnical Report May Include
The exact contents depend on the agreed scope and the information obtained during the investigation.
Site Setting
Description of the site, previous uses, surrounding land, geology, hydrogeology and environmental setting.
Ground Conditions
Summary of the encountered strata, made ground, groundwater observations and relevant laboratory results.
Ground Model
An interpretation of the likely below-ground conditions and their relevance to the proposed development.
Foundation Advice
Recommendations regarding suitable foundation solutions, founding depths and other geotechnical considerations.
Contamination Assessment
Evaluation of identified contamination risks and whether remediation, further testing or validation may be necessary.
Construction Considerations
Advice relating to excavations, groundwater, floor slabs, drainage, earthworks and other relevant construction risks.
Information Required for a Quotation
To prepare an accurate quotation, the consultant will usually need the full site address, a description of the proposed works and available drawings showing the site and proposed development.
It is also helpful to provide any planning conditions, Building Control comments, warranty-provider requirements, previous ground reports, structural proposals or known details of the site's former use.
Nationwide Geotechnical Site Investigations
One Stop Consult coordinates geotechnical and environmental investigation services for residential, commercial, industrial and mixed-use developments throughout mainland UK. The appropriate consultant and investigation method are selected according to the site location, proposed development and required scope.
Other Services Your Project May Require
Ground investigation is often coordinated alongside structural, environmental, drainage and regulatory services.
Important Geotechnical Information
The appropriate investigation scope, fieldwork methods, laboratory testing and recommendations are project-specific. Conclusions are based on the information available and the ground conditions encountered at the investigation locations. One Stop Consult provides consultancy and coordination support through its specialist geotechnical and environmental consultant network.
Geotechnical Site Investigation FAQs
What is a geotechnical site investigation?
It is an assessment of the ground beneath a proposed development. It can include desk research, site inspection, intrusive investigation, sampling, laboratory testing and recommendations for design and construction.
What is the difference between a Phase 1 and Phase 2 investigation?
A Phase 1 Desk Study reviews existing information and potential risks without disturbing the ground. A Phase 2 investigation involves physical site works, sampling and testing to establish the actual ground conditions.
Do I need a Phase 1 before a Phase 2 investigation?
A Phase 1 is commonly completed first because its findings help design a proportionate and targeted Phase 2 investigation. However, the correct approach depends on the project and available information.
Can the investigation provide foundation recommendations?
Yes, where the investigation scope and information obtained are sufficient. The report may advise on foundation type, depth, bearing conditions and other relevant ground-design considerations.
How long does a site investigation take?
Timescales depend on the investigation method, laboratory testing and whether monitoring is required. Straightforward projects may be completed relatively quickly, while more complex sites can take longer.
Can you help with a contaminated site?
Yes. The investigation can assess potential contamination and, where necessary, support remediation strategy, verification testing and validation reporting.
Do you provide geotechnical investigations nationwide?
Yes. We coordinate suitable geotechnical and environmental consultants for eligible projects throughout mainland UK.
Request Your Free Geotechnical Investigation Quote
Complete the form below with the site address, proposed works and current project stage. Upload any available drawings, planning information or previous reports so our team can review the requirements and coordinate an appropriate quotation.