What Are Post-Tension Cables?

Post-tensioning is a construction technique that strengthens concrete slabs. After the concrete is poured, steel tendons encased in plastic sheaths are tensioned (pulled tight), compressing the slab and allowing for longer spans, thinner slabs, and fewer support beams. You’ll find post-tension systems in everything from multi-storey apartments to commercial towers and bridges.

But, with all that built-in tension comes one major caveat: PT cables must never be damaged.

Why Are Shallow PT Cables a Growing Concern?

Traditionally, PT cables sit below a layer of rebar, embedded deep enough that accidental contact is rare. But on an increasing number of sites, our field teams are encountering shallow installations—well outside the norm.

That poses a big problem.

Contractors might assume a safe drilling or coring depth, but a shallow PT cable can turn a routine job into a catastrophic event. The costs of repair are steep—but the risk to life is even higher.

This Is Where Xradar Comes In

Xradar’s methodology and training academy was built to help technicians detect what others miss. We don’t just scan concrete—we provide certainty. Our advanced concrete scanning techniques allow us to precisely identify PT cables, distinguishing them from rebar, conduits, and other in-slab features. And most importantly, we can do this without disrupting your site’s schedule.

Here’s what sets Xradar apart:

  • High-accuracy scanning that pinpoints PT cable locations—even at shallow depths.
  • Accurate depth measurements to plan safe drilling, coring, and anchoring.
  • Detailed markups (on-site) and digital reporting that reduce rework, delays, and liability.
  • Guaranteed accuracy, backed by years of specialized experience in high-risk concrete environments.

When Should You Scan Concrete?

If you’re planning to:

  • Core through a slab
  • Install anchors
  • Drill for mechanical, electrical, or plumbing work

…you need to scan first. Xradar are the most advance concrete scanning team in Canada, and will confidently handle your project.

We’ve protected thousands of projects across Canada, and with PT cable placement becoming increasingly unpredictable, concrete scanning is no longer optional—it’s essential.

Don’t Take the Risk

PT cable strikes are preventable, and concrete scanning is your best line of defence. Visit our Concrete Scanning Services page to learn more, or speak directly with our team. We look forward to keeping your concrete structure safe, efficient, and built to last.

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    The Importance of Detecting Post-Tension Cables Before Drilling

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