Concrete Scanning Services

No. We cannot eliminate risk. Utility locating is a risk-mitigation measure, not a risk-elimination measure. However, the more information that we have available — private site plans, civil construction plans, and complete site access — the greater the likelihood of success.

That depends. Conductive utilities, such as electrical and copper telecommunications services, are relatively easy to trace. For polyethylene water or gas lines, we rely on ground-penetrating radar, which does not guarantee successful location every time and is highly dependent on the work area, surface, and soil type. Sometimes these utilities are laid with tracer wires, which make them easy to locate. For sewer and stormwater lines, we generally need access to a manhole or inspection opening to insert a trace rod.

We locate fibre-optic cables using a trace rod inserted into the cable duct, as fibre-optic lines are non-conductive.

That depends on the quality of the signal our transmitter generates. If we have a strong, consistent, round signal, we are confident of the utility's position. If the area is heavily congested with utilities, overhead power lines, temporary fencing, or other signal impediments, our accuracy can be affected.

AS5488, the Australian Standard that governs subsurface utilities information, provides a 300mm width tolerance and a 500mm depth tolerance on site markings. We can generally locate utilities to within a far more accurate degree; however, it is worth noting these tolerances before excavating.

Quality levels (QL) range from A (most accurate) to D (least accurate). Think of them as degrees of confidence rather than accuracy.

• QL-A — the utility has been potholed and physically verified.
• QL-B — a strong, consistent EMF reading with a verified depth.
• QL-C — visual surface features confirming a utility's location, but no EMF or GPR readings.
• QL-D — no information beyond the site or BYDA plans.

We receive this question quite a lot. Dial-before-you-dig is now BYDA (Before You Dig Australia). BYDA provides free utility plans to the public; however, these are QL-D and require a skilled locator to inspect the site and physically locate the utilities.

It depends on the site context. We generally rely on ground-penetrating radar to find water pipes; however, site context and depth matter. If we are looking for a 20mm polyethylene line in a front garden, we can likely find it. Under reinforced concrete, the likelihood drops significantly.

We often recommend potholing water utilities when an accurate location is required and conventional methods such as EMF and GPR have been unsuccessful.

Generally, yes. If you are building near public infrastructure that traverses your property, you need a utility location report from a certified locating organisation to the QL-B standard, confirming depth, orientation, and distance from the property boundary. You will need this to submit a build-over application (BOA).

We need to confirm access to a manhole before attempting to trace the utility. If you have a sewer manhole on your property, great — if not, you may need to arrange access through your neighbours.

Our handheld GPR systems can scan most concrete slabs and provide information on reinforcement bar configuration, slab depth, concrete cover, and the presence of post-tensioned cables, embedded conduits, and anomalies such as voids or honeycombing.

As a rule, we can achieve a depth of around 500mm; however, the GPR signal attenuates the deeper it scans and the more heavily congested the slab. For heavily reinforced podium slabs, we rely on alternative testing methods such as UPE.

UPE stands for Ultrasonic Pulse Echo testing. It is a non-destructive testing (NDT) method that uses high-frequency sound waves to inspect the internal structure of concrete by emitting pulses and analysing echoes from defects or boundaries. It enables scanning from one side to identify subsurface voids, cracks, and thickness — very useful for detecting anomalies at depths beyond the reach of GPR.

Unfortunately, there is no defensible way to determine reinforcement bar diameter using NDT alone. We use a Proceq PM8000 Profometer (cover meter reader) to obtain bar diameter estimates; however, these are subject to several limitations, including a maximum concrete cover depth of 63mm. If you require a specific diameter, you must take a core sample or break out a section of concrete.

Yes. Using a combination of GPR and UPE, we can easily identify voids. A common request is to check Besser-block walls for voids due to insufficient concrete vibration, or to check slabs for voids or cold joints where the concrete pour was staged.

Yes, absolutely. Our investigations can provide engineers with critical information about reinforcement layout, internal defects, and anomalies such as voids and delamination. Our detailed reports assist with structural assessments, remediation planning, and asset management strategies.

Yes. We have conducted many asphalt thickness assessments for major clients and are well-versed in the methodology. We use high-frequency radar and specialised data analysis to determine accurate asphalt thicknesses as part of road or deck-wearing-surface assessments.

We have two methodologies. We use a Proceq Silver Schmidt Rebound Hammer to test surface hardness — a spring-loaded tool that analyses rebound responses. Where a definitive MPa value is required for an engineering assessment, we scan the slab, identify suitable coring locations, remove 3–4 core holes and send them to a laboratory for testing. This destructive method is the most accurate way to measure concrete's MPa.

There are multiple reasons why concrete might crack. The size and path of cracks often indicate whether the cracking is geotechnical (soil-related), curing- or expansion-related, or related to reinforcement bar placement. Our scanning assessments can help narrow down the cause by providing key insights including concrete cover depth, whether mesh was correctly placed, or whether there is a moisture or groundwater issue.

There are many reasons why moisture may leak through a slab. Water intrusion through concrete floors may result from hydrostatic pressure, slab cracks, rising damp, poor waterproofing, or leaking services beneath the structure. Subsurface investigations can help determine whether moisture is coming from beneath the slab or from within the concrete structure itself.

A sagging slab typically results from a loss of support. Possible causes include soil erosion, leaking pipes (commonly stormwater), poor soil compaction, and voids beneath the slab caused by soil washout or an incorrect concrete mixture. Our subsurface diagnostic strategies can help identify the exact cause of the sag.