Money spent before the project is approved, on a project that might not proceed. It is also the cheapest insurance available on the most irreversible part of the build.
| Item | What we are establishing |
|---|---|
| Access | Can a rig physically reach the drilling location, and what does it cost to get it there and put the site back |
| Available area | Setbacks from structures, property lines, septic and services; whether horizontal is even an option |
| Buried services | Locates before anything is drilled or trenched. Non-negotiable. |
| Geology | Expected overburden depth and rock type, from well records and local experience, confirmed by the test bore |
| Groundwater | Whether an open loop is viable, and whether water is a drilling complication |
| Load and balance | The building's annual heating and cooling profile, which sets field size as much as peak load does |
| Plant location | Where the equipment sits, and how the loop gets from the field into the building |
On a commercial loop field, this is the difference between a designed system and an expensive guess.
A test bore is drilled to the intended depth and instrumented. Heat is injected at a known rate and the response is logged over a sustained period — typically a couple of days. From that you get the ground's actual thermal conductivity and undisturbed temperature at that specific location.
Those two numbers drive the entire field design. Assume them, and you are sizing the most expensive and least reversible component of the project on a value taken from a table.
A test costs a fraction of one borehole. A field sized on an over-optimistic assumed conductivity can be short by several boreholes — discovered years later, on an occupied building, at many times the price.
It can also work the other way. Where the ground performs better than the table assumed, the test pays for itself immediately by removing boreholes from the design.
On a small residential system the cost of the test is disproportionate to the field, and good practice is to design conservatively from local well records and known geology instead. We will tell you which category your project is in rather than selling a test to every enquiry.
The bore itself is quick. The test needs a sustained period, typically a couple of days of logging, because you are measuring how the ground responds over time rather than taking an instantaneous reading.
No — it is normally incorporated into the finished field, so the drilling is not lost even though the test time is an additional cost.
A feasibility conversation and a site visit are part of quoting. A full instrumented thermal conductivity test is a separate scope of work, because it involves a rig and several days of logging.
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Tell us the building, the site and how long you expect to own it. If ground source is wrong for you, that is the first thing we will say.