How long does a concrete scan take?

Concrete scan duration depends on the scope of the work, but typical UK jobs fall into reasonably predictable bands.

Typical durations

• Small pre-drill scan, 5–10 target points on one slab. 1–2 hours on site, plus travel and reporting. Usually quoted as a half-day attendance.
• Reinforcement-mapping survey of a typical slab area (50–100 m²). 3–5 hours on site. Half- to full-day job.
• Post-tension scan over a similar area. Full-day attendance — denser scanning pattern, more careful interpretation.
• Multi-element campaign (several columns, beams, walls). 1–2 full days, depending on scope.
• Large-scale GPR on a site with vehicle-towed array. Single-day field work plus processing and interpretation.

Reporting time

The on-site time is one part:

• On-slab markup the same day. Standard for pre-drill work.
• Next-morning written report. Standard for most jobs.
• Multi-day reporting for larger or more complex work.
• Same-day report on request sometimes available with notice.

Factors that compress the timeline

• Surface clean and accessible before attendance.
• Brief marked up in advance.
• Pre-induction completed.
• Scope tightly defined.
• Adjacent work combined into one visit.

Factors that extend the timeline

• Surface preparation done on the day.
• Brief unclear or shifting on site.
• Access not ready (lifts, MEWPs, scaffolding).
• Findings prompt extended coverage.
• Multi-format deliverables that add reporting time.

A useful rule of thumb

• Half-day attendance for a small focused job.
• Full-day attendance for typical reinforcement-mapping or PT detection.
• Multi-day attendance for site-scale work or paired-method campaigns.

Reporting follows attendance by 1–2 working days for a typical job.

What to plan for in your programme

If you are scheduling concrete scanning into a project programme:

1. Slot a half- or full-day on-site, depending on scope.
2. Allow 1–2 working days for reporting before downstream work depends on the report.
3. Build in contingency for findings that prompt extended coverage.
4. Plan access ready for the day — survey time is wasted if access is not.

Specifically for pre-drill work, schedule the survey to be complete and signed off before the drilling team arrives. Stacking drilling on the same day as scanning is rarely efficient unless there is a defensible buffer.

For a fuller treatment of survey timing, see How long does a GPR survey take.