Virtual Trial Holes

Virtual trial holes, also known as digital trial holes or virtual trenching, offer a way to assess underground utilities without physical excavation. Subvision Surveys uses GPR and geophysical imaging techniques to build a detailed picture of subsurface conditions, without the need to dig.

Traditional trial holes require excavation at every point of interest, which takes time, disrupts the site, and carries inherent risk when working near live utilities. A virtual trial hole replaces this with non-invasive detection, giving you the same information on utility position, depth and, where possible, an indication of type, without breaking ground. This is particularly valuable on live sites, in areas with restricted access, or where the cost and disruption of multiple physical trial holes would be difficult to justify.

How We Build a Virtual Trial Hole

By analysing data collected through GPR and other non-invasive detection methods, our team accurately determines the location, depth and condition of underground utilities across a site. This approach reduces cost and programme delay compared with physical trial holes, while improving site safety by minimising excavation risk, particularly on live or congested sites where digging carries its own hazards.

Interpreting Complex Ground Conditions

Where ground conditions or utility density make GPR interpretation more complex, our surveyors draw on experience across a wide range of site types to interpret the data with confidence, rather than relying on the equipment alone. Factors such as soil type, moisture and utility clustering can all affect signal clarity, and knowing how to read around these variables is what separates a reliable virtual trial hole from raw, unverified radar data.

Our team of experienced surveyors record all information topographically, providing an AutoCAD survey plan and cross-section detail your design team can work with directly. This gives you a clear, accurate record of utility position relative to other site features, ready to feed straight into design and planning without further interpretation on your end.

Why Choose Subvision for Virtual Trial Holes?

Subvision Surveys is SSIP and ISO accredited, and our team delivers virtual trial holes for Tier 1 contractors, developers and planners across London, the South East and nationwide. Because we carry out both the GPR detection and the topographical recording ourselves, your survey plan and cross-section data come from a single site visit and a single team, rather than being reconciled from separate providers. Virtual trial holes can also be combined with our Desktop Utility Search Packs, wider utility clearance and PAS128 Utility Mapping Surveys for a complete picture of utility risk, from early feasibility through to detailed site verification.

Contact Subvision Surveys today to discuss virtual trial holes for your project.

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VIRTUAL TRIAL HOLES FAQ’S

At Subvision Surveys, our virtual trial holes provide a non-intrusive way of investigating underground services and features without physically excavating the ground. Using specialist surveying technology, our experienced team can collect information about what is beneath a site and use this to help establish the likely position and depth of underground infrastructure. Virtual trial holes can provide valuable information for architects, engineers, developers and contractors when planning construction or excavation works. By carrying out this investigation before work begins, our team can help clients gain a better understanding of the existing ground conditions and underground services, reducing the need for unnecessary disruption to the site.

Our virtual trial hole surveys can be useful when you need information about underground services but want to minimise the need for physical excavation. Before construction or groundworks begin, understanding the position and depth of existing services can be extremely important. Our team can use specialist surveying techniques to investigate below the surface and provide information that can support design and planning decisions. This can be particularly useful on development sites, construction projects and areas where excavation may be disruptive or difficult. At Subvision Surveys, we tailor our approach to the requirements of your project, helping you obtain useful underground information before work begins.

Our team can use virtual trial hole investigations to provide information about the likely location and depth of underground services and features. Depending on the site and the information available, this can include services such as drainage, utilities, cables, pipes and other buried infrastructure. The exact information we can obtain will depend on factors including the site conditions, the technology used and the nature of the underground feature being investigated. Our experienced surveyors assess each project individually and use the appropriate surveying methods to collect the required information. We then provide clear survey data that can help your design and construction team understand the existing site.

Our virtual trial hole surveys use specialist surveying technology to investigate below the ground surface without the need to physically excavate a trial hole. Our experienced surveyors collect measurements and information from the site and use this data to establish the position and depth of relevant underground features. The technology and survey methods used will depend on the requirements of the individual project and the conditions present on site. Our team combines the information gathered with more than 25 years of surveying experience to interpret the results and provide useful information for your project. This approach can help reduce unnecessary excavation while improving your understanding of the ground.

Virtual trial holes can be particularly useful during the planning and design stages of construction and development projects where information about underground services is required. Our team can carry out investigations before excavation or other groundworks begin, helping your project team understand what may be present beneath the surface. They can be valuable where traditional trial holes would cause disruption to existing surfaces, landscaping, roads or other areas of a site. Our team works with clients to understand the information they need and determine whether a virtual trial hole approach is suitable. We aim to provide practical information that can support safer and better-informed project planning.

Our team provides virtual trial hole surveys for both domestic and commercial clients, depending on the requirements of the project. We work alongside developers, engineers, architects, contractors and other construction and property professionals who need reliable information about underground features. Our services can be used on a variety of sites, from smaller development projects through to larger commercial and infrastructure schemes. We understand that every project presents different challenges, which is why our experienced surveyors take the time to understand your requirements before carrying out the investigation. This allows us to provide an approach that is appropriate for your site and the information your project needs.

At Subvision Surveys, our team combines more than 25 years of surveying experience with modern technology and specialist surveying techniques. We understand the importance of having reliable information about underground services before excavation and construction work begins. Our virtual trial hole surveys provide a non-intrusive approach to investigating below-ground features, helping our clients reduce unnecessary disruption while gaining valuable information about their sites. From your initial enquiry through to completing the survey, we focus on accuracy, professionalism and clear communication. Whether you’re a homeowner, developer, engineer or contractor, our experienced team will work with you to understand your requirements and provide a surveying service tailored to your project.

Have Any Questions?

If you have any questions regarding our services feel free to contact the Subvision team.