GPR Services · Peace Country
Slab Thickness & Void Detection in Fort St. John, BC
Find the washout before it becomes the sinkhole. GPR measures slab thickness and images the voids beneath floors, decks, and pavements. Serving Fort St. John and the Peace Country region with certified technicians, non-invasive methods, and insurance-ready documentation — since 1999.
Free phone consult · No pressure · Mon–Sat 8am–6pm PT
Fort St. John ground conditions & what they mean for GPR
Local geology: Fort St. John sits on Peace plateau clays with deep seasonal frost. Clay attenuation plus metre-plus frost defines northern survey planning — summer windows give the best returns, and frost-depth services sit deeper than anywhere else in BC.
Local building stock: Energy-sector service city — industrial yards, work camps, and newer subdivisions built to northern frost specs.
Common slab thickness & void detection work in Fort St. John
- Industrial yard utility mapping
- Deep frost-line service locating
- Subdivision pre-dig locates
- Soft spots in floors
- Pre-sinkhole investigation
- Slab QA verification
How the Fort St. John site visit works
- 1
Grid scan
The slab is scanned in a tight grid; thickness reads continuously and voids appear as distinctive reflections beneath.
- 2
Void boundary mapping
Any void's footprint is walked out and marked so the repair fills the whole cavity, not just the symptomatic corner.
- 3
Cause assessment
Voids have causes — leaking pipes, washed fill, settling organics. We correlate with leak findings so the fix addresses the source.
- 4
Report
Thickness map, void extents, and probable cause delivered for the engineer or contractor handling remediation.
Fort St. John questions, answered
The floor sounds hollow when we walk on it. Is that a void?
Often, yes — a drummy slab is the classic early sinkhole symptom. GPR confirms in minutes whether there is a cavity, how big it is, and how thin the remaining slab bridge is. That last number decides whether the area gets barricaded today or scheduled for repair next month.
What causes voids under BC slabs?
The usual suspects: leaking water or sewer lines washing out fines, poorly compacted fill settling, buried organics decomposing, and in older Vancouver Island areas, karst dissolution in limestone. Identifying which one drives the repair approach.
Can you verify a new slab was poured to spec?
Yes — GPR thickness verification is the non-destructive alternative to coring. Continuous profiles across the pour show exactly where thickness meets or misses the structural drawing, with ±5 mm accuracy.
How urgent is a confirmed void?
Depends on span and bridge thickness, which the scan quantifies. A 30 cm void under a 150 mm slab is monitoring territory; a 2 m void under 80 mm of bridging concrete is a barricade-now finding. The report states which case you have.
How deep can GPR scan in Fort St. John?
Fort St. John sits on Peace plateau clays with deep seasonal frost. Clay attenuation plus metre-plus frost defines northern survey planning — summer windows give the best returns, and frost-depth services sit deeper than anywhere else in BC. We select antenna frequency to match — and where local ground limits radar depth, we pair GPR with electromagnetic locating, acoustic methods, or tracer gas so the survey objective is met regardless of soil conditions.
Do you actually work in Fort St. John, or dispatch from elsewhere?
Fort St. John is part of our standing Peace Country service area — the same certified technicians and equipment that cover the rest of the region. Scheduling is typically within 24–72 hours, with same-day response often possible during business hours (Mon–Sat, 8am–6pm Pacific).
What does slab thickness & void detection cost in Fort St. John?
Pricing matches our province-wide structure — no regional premium for Fort St. John. Most residential-scale work falls in the $350–$1,200 range depending on scope; commercial and multi-site projects are quoted after a free phone consult. Call 604-239-9934 and we will give you a tight estimate in five minutes.
Other GPR services in Fort St. John
Slab Leak Detection in Fort St. John
GPR maps the in-slab plumbing and rebar so thermal and acoustic findings convert into a single small repair patch — not a jackhammered floor.
View serviceSewer Leak Detection in Fort St. John
GPR finds the voids and washouts that leaking sewers carve around themselves, while CCTV confirms the failure from inside the pipe.
View serviceConcrete Scanning in Fort St. John
The full picture inside any slab, wall, or beam — rebar, PT cables, conduits, voids, thickness — imaged at 1.6 GHz before a single cut.
View serviceParking Garage Slab Scanning in Fort St. John
Parkade decks fail from the inside — chloride-corroded rebar, delamination, membrane leaks. GPR maps the deterioration before the spalling starts.
View service← All about slab thickness & void detection·All GPR services·GPR guide
Slab Thickness & Void Detection near Fort St. John
Need slab thickness & void detection in Fort St. John?
Free phone consult with a certified GPR technician — we will tell you whether a survey is warranted and quote it in five minutes. No pressure.