A 20-ton truck-mounted rig with a hydraulic pushing system, cone penetrometer, and continuous data acquisition module. That is what arrives on site for a CPT in Whitby. No drilling, no spoils, no waiting for lab results. We push an instrumented cone into the ground at a constant 2 cm/s and get real-time tip resistance, sleeve friction, and pore pressure. In Whitby’s glacial till and Lake Iroquois plain deposits, this speed matters. You avoid the delays that boreholes bring and get continuous soil profiles without gaps. For projects near the 401, in Brooklin, or along the waterfront, we often pair the CPT with an SPT drilling program when you need both continuous data and physical samples for index testing.
A CPT log from Whitby’s Lake Iroquois plain deposits will show you every sand seam and clay band without the disturbance of a split spoon.
Technical details of the service in Whitby
Typical technical challenges in Whitby
Whitby sits at roughly 90 m elevation, with deeper deposits of soft clay closer to Lake Ontario. The town’s population has passed 140,000, and pressure on land means more building on marginal soils. The main risk here is missing a thin sand layer within a clay profile that acts as a drainage path, or worse, a liquefiable lens under seismic load. NBCC 2020 seismic hazard values for southern Ontario are not negligible. A CPT without pore pressure measurement misses that drainage signal. We run piezocone as standard. If you skip the CPT and rely only on SPT logs, you get data every 1.5 m. A 30 cm sand seam between blows stays invisible. That seam can cause differential settlement under a footing or slope failure in an excavation.
Our services
We run two core CPT configurations in Whitby, depending on site conditions and project scope.
Standard Piezocone (CPTu)
Measures cone tip resistance (qc), sleeve friction (fs), and pore water pressure (u2). Used for soil classification, undrained shear strength, OCR, and permeability estimates. The standard test for most foundation and embankment projects.
Seismic CPT (SCPTu)
Adds a geophone module to measure shear wave velocity (Vs) at regular intervals. Direct input for NBCC site class determination and liquefaction triggering analysis. Specified when seismic site classification is required.
Frequently asked questions
How much does a CPT test cost in Whitby?
Mobilization plus testing typically ranges from CA$240 to CA$290 per meter for a standard piezocone in Whitby, depending on depth and site access. Seismic CPT adds about 15-20%. We provide a fixed quote after reviewing the site location and target depth.
How deep can you push the cone in Whitby's soils?
In Whitby's glacial till we usually reach 20 to 25 meters before refusal. In softer Lake Iroquois clay deposits near the lake, we can push deeper, but we stop when the cone tip resistance indicates dense till or bedrock. We monitor sleeve friction continuously to judge refusal.
Do I still need a borehole if I do a CPT?
A CPT gives you a continuous soil profile but does not recover physical samples. For environmental sampling or detailed index testing, you still need at least one borehole. We often pair a few CPT soundings with one targeted borehole to get the best of both methods.
Is the CPT accepted for Ontario Building Code site classification?
Yes. Seismic CPT data providing shear wave velocity (Vs) profiles is accepted under the OBC and NBCC for determining Site Class. We provide the Vs profile and site class recommendation directly in the report.