Non-destructive slab surveys · Sydney sites
Concrete Scanning Sydney
Every slab hides something: reinforcement, tensioned cables, electrical conduits, pipes. Striking any of them with a core drill or saw turns a small job into an expensive one, and a severed post-tension cable can be dangerous the instant it lets go. Book a scan before the blade touches concrete.
Concrete scanning is an interpretive skill, not just a piece of equipment: ask any operator about their training, their experience on your slab type and how they express confidence in their marks. For excavation work, lodge a free enquiry with Before You Dig Australia and keep the plan responses on hand; field locating complements those plans rather than replacing them.
Site coverage
Precincts and project zones across Sydney
Slab construction differs by precinct: post-tensioned towers in the city, raft slabs in the growth areas, heavy industrial floors in the south. Choose your zone for what scanning there usually involves.
CBD and city fringe
Sydney CBD, Barangaroo, Pyrmont and the inner commercial ring
Area detailParramatta and the western corridor
Parramatta, Westmead, the Hills and the north-west growth belt
Area detailSouth Sydney and industrial precincts
Alexandria, Botany, the airport precinct and the southern industrial belt
Area detailScanning services
Know what is in the slab before you cut
Pre-cut and core scanning
Marking reinforcement, cables and conduits at the exact locations where penetrations are planned.
Post-tension cable location
Tracing stressed tendons in post-tensioned slabs so penetrations keep a deliberate offset.
Conduit and in-slab service tracing
Finding live electrical conduits, plumbing and heating pipes cast into concrete before they are struck.
Underground utility locating
Locating buried services around the site, working from Before You Dig Australia plans outward.
Slab profile and void scanning
Measuring slab thickness, reinforcement layout and sub-slab voids without breaking the surface.
Straight answers
Scanning questions
Is GPR the same as X-ray scanning?
No. Ground-penetrating radar works from one side of the slab, involves no radiation and delivers results on the spot, which makes it the default for construction scanning. Concrete radiography, X-ray: offers finer resolution in heavily congested elements but needs access to both faces and a radiation exclusion zone while the source is exposed, so it is reserved for special cases.
Can a scan miss something?
Yes, and honest operators say so. Radar returns degrade in wet or very thick concrete, closely spaced bars can shadow deeper targets, and non-conductive plastics are harder to distinguish. Good practice manages that risk (sweeping in two directions, marking conservatively and flagging low-confidence zones) but no survey method sees everything.
What happens if someone cuts a post-tension cable?
The stressed tendon can release violently, damaging the slab and endangering anyone nearby, and the structural repair that follows is disruptive and costly. That risk profile is why builders treat scanning before penetrating a PT slab as a fixed rule rather than a precaution.
Do I still need Before You Dig Australia if I book locating?
Yes. The BYDA enquiry is free and provides asset owners' plans and conditions, some of which are mandatory to obtain before excavating near their networks. Field locating then tests those plans against reality, and covers the private services the plans never show.
How accurate are the depth readings?
Depth from GPR is an estimate calibrated against material properties, and concrete varies. Horizontal position marks are typically strong; depth figures should be treated as guidance with a tolerance, which is why penetration depth limits get set conservatively.
Do you scan walls and soffits or just floors?
Suspended slabs, walls, columns and soffits can all be surveyed, access permitting. Overhead work is slower and marking conventions change, but the physics is the same, the survey is planned around what the trade needs to cut and from which face.
Treat every unidentified object in a slab as live and every unmarked area as unscanned. If a cut nicks a conduit or a tendon, stop work, keep people clear of the slab face and get the relevant specialist on site before anything else happens.
How it works
From booking to marked slab
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01
Describe the penetration work
What is being cut or drilled, where, how deep, and into what kind of structure, plus drawings if they exist. That determines the method mix and the time on site.
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02
Get a scoped booking
The booking confirms the survey method, the areas covered, site induction requirements and what the deliverable is: field markings, photos or a written report.
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03
Scanning and marking on site
The operator sweeps each area, interprets returns in real time and marks targets and exclusion zones directly on the surface where the trades will work.
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04
Deliverable and follow-up
Markings are photographed before the site takes over, and any requested report or field record is issued so the evidence survives after the marks are ground away.
Scanning services
Tell us about the job
Send through the job details and we'll connect you with a licensed provider who can quote this work.
If this is an emergency or anyone is at immediate risk, contact the relevant emergency service or your network or utility operator directly instead of using this form.