Ground Investigation

Yes. If you are building new foundations, extending an existing building, or working in areas with ground risks such as clay soils or trees, a geotechnical investigation is usually required.  

Many planning authorities including building control make it a condition of approval, and structural engineers will typically require geotechnical data before they can design foundations. 

We will usually require two weeks from receipt of formal instruction to mobilise on site depending on the scale of the investigation.  

The geotechnical analysis on soils will take up to four weeks after submission of the last soil sample, with further time needed if groundwater monitoring in borehole wells is necessary. 

Typically, we suggest allowing 6 to 8 weeks for a small to medium ground investigation, longer if the site is large and/or has numerous constraints. 

A geotechnical investigation assesses the engineering behaviour of the ground, whereas a geo-environmental investigation considers the potential for contamination and its associated risks. Both are often needed to properly inform development.  

• Geotechnical investigations determine the strength, stability, and drainage characteristics of soils and rocks. The results are used by engineers to design safe and efficient foundations, retaining walls, and infrastructure.  

• Geo-environmental investigations evaluate whether a site has been impacted by past land uses, such as fuel storage, industrial activity, or waste disposal. They assess risks to human health, controlled waters, and buildings, and determine if remediation is required. 

We will assess the testing requirements of your site as well as any access restrictions when we prepare our Ground Investigation proposal. Our experienced engineers and consultants have worked on a range of sites where access restrictions have been overcome. 

A geotechnical investigation should not commence and no ground broken until the location of all known services has been determined as they pose a significant health and safety risk.  

If up-to-date plans are not available, we recommend requesting them from the utility companies. If timescales are tight, we recommend a specialist service clearance survey (in line with PAS 128 British Standards) which can be combined with a level survey or a topographical survey if required.  

Enough time should be allowed to reduce the risk of a service strike, as we are unable to be held responsible for any private or public service strike we were not made aware of in advance.  

Yes. We frequently combine geotechnical investigations with Phase 2 Site Investigations to form a single geo-environmental investigation.  

This is more efficient and cost-effective, as both the contamination and engineering aspects of the ground can be assessed using the same site mobilisation, exploratory holes, and laboratory testing programme.