Concrete Core Testing in Ontario: Owners’ Report Requirements

For an Ontario concrete-strength investigation, ask for an engineer-directed sampling plan, location-linked core IDs and a signed laboratory report: a recommended handoff package, not a province-wide statutory minimum established by the Ontario specifications cited here.[1][2][5]

Separate project requirements from recommended records

Core-strength testing measures the compressive strength of a specimen drilled from existing concrete. Its dimensions, preparation and moisture condition can affect the result, so the strength number needs supporting records.[5] Organize the order into three categories:

• Project requirements: Ask the engineer to identify the governing specification, test method and edition, interpretation basis and applicable approval conditions. Do not copy requirements from an unrelated specification; QuollNet’s general technical guide distinguishes the applicable project standard from other testing and interpretation systems.[5]
• Recommended traceability records: Request a sampling plan, drawing-linked locations, unique core IDs and records of orientation, dimensions, condition and preparation. These follow QuollNet’s guidance, rather than an Ontario-wide legal checklist.[5]
• Agreed deliverables: Specify a signed laboratory report, its recipients and delivery date, and the separate scope for the engineer’s interpretation.

Toronto’s TS 1350 addresses municipal concrete work, including road bases, curbs, sidewalks and streetcar track work—not a general existing-building core-report package.[2] Ontario’s draft OPSS.PROV 203 concerns rock stabilization, including shotcrete and concrete buttresses.[1] Ask the engineer whether either document is relevant before using it in the order.

Verify that the laboratory quote covers drilled concrete cores

Describe the service as “compressive-strength testing of drilled cores from existing concrete, using the engineer-selected test method”, rather than simply “concrete testing”. This distinguishes the requested specimen and method from other concrete laboratory services.[4][5]

Paterson Group lists CSA A23.2-14C core testing and offers a quote-request option. Its separate ASTM C597 ultrasonic pulse velocity service estimates concrete quality by measuring compression-wave velocity; it is an indirect method, not drilled-core compression testing.[4]

Soil-Mat advertises a CCIL Type Q concrete-testing laboratory and lists concrete-cylinder, mortar, grout and bedrock-core compression services.[3] Ask it to confirm drilled-concrete-core testing explicitly rather than treating those listings as confirmation of the required scope.

Before accepting a quote, request written answers covering:

• Method: Does the service match the core-testing method selected by the engineer?[4][5]
• Preparation: What specimen preparation and moisture conditioning are included, and will they be recorded?[5]
• Extraction and transport: Who arranges drilling, identifies the cores and delivers them while preserving their location references?[5]
• Reporting: Will the report retain core IDs, specimen details, results and corrections, with the requested signature and delivery to the engineer?[5]

Ask Paterson and Soil-Mat for details of their service territories and packages.[3][4] Confirm coverage for the project address and the precise scope with each laboratory.

Get the engineer’s sampling instructions before drilling

QuollNet recommends defining the sampling scope, specimen dimensions, location records and interpretation procedure before drilling.[5] Ask the engineer to turn those decisions into written instructions rather than leaving the crew to choose convenient locations.

• Investigation question and coverage: Identify what the investigation needs to resolve and which member and region the samples will represent.[5]
• Sampling layout: Have the engineer specify the number and distribution of cores, target diameter and length, and drilling orientation—not adopt a generic quantity or size from an online guide.[5]
• Location record: Request a marked drawing or equivalent record assigning each location a unique reference linked to the element, grid or coordinates, elevation and drilling direction. Include the relationship to the original pour or batch where established.[5]
• Embedded items: Plan to locate reinforcement, tendons and services using a scanner or another appropriate method. QuollNet advises against cutting reinforcement or prestressing unless the responsible structural professional has assessed and explicitly approved it.[5]
• Hole repair: Include the repair approach for every hole in the plan.[5]

Name who approves locations and handles changes if embedded items or site conditions prevent the planned extraction. Ask for revised locations to be approved and marked before proceeding, so the location record follows the work performed.

Keep core IDs linked through extraction and laboratory receipt

Carry each location reference onto the extracted core and into the laboratory report—not just onto the drilling plan. QuollNet recommends keeping identity, location and preparation history connected throughout testing.[5]

Use a recommended record for each core, with these technical fields:

• Identity and location: Project and structure identification, unique core ID, drawing/location reference, member, elevation and drilling direction.[5]
• Extraction: Extraction date, photographs and observations of orientation, cracks, voids and visible reinforcement, linked to the core ID.[5]
• Laboratory continuation: Measured diameter, tested length, preparation and moisture-conditioning records, retaining the same ID in the report.[5]

Illustrative record: Core ID SLAB-A → drawing reference SK-A, marked location Alpha → photographs labelled SLAB-A → laboratory specimen and report entry SLAB-A. This illustrates identification, not a drilling location or compliance with a standard.

A label such as “Core 1” needs a location link: QuollNet warns that strength can vary with exact location and vertical position within a member.[5]

Agree who labels, transports and receives the cores, and who resolves unreadable labels or mismatches. Optional administrative controls include transfer names and dates, a receipt check against the core list and a route for reporting discrepancies. Treat these as agreed project controls, not an official Ontario custody form; QuollNet addresses traceability but does not establish such a form.[5]

Specify the signed laboratory report

Ask the laboratory to use the sampling record’s core IDs so each result remains linked to its location. QuollNet recommends the following reporting information; use it as a requested checklist, not a universal Ontario template.[5]

• Identification: Project and structure, member, exact sampling location, core ID, drilling orientation and linked photographs.[5]
• Specimen history: Extraction and testing dates, observed cracks, voids or reinforcement, preparation and moisture conditioning.[5]
• Test details: Diameter, tested length, governing test method and disclosure of standard-permitted corrections applied.[5]
• Results: Maximum load and reported compressive strength, separate from the engineering assessment or acceptance basis.[5]

These details help explain the number: geometry, preparation and moisture condition can influence measured strength. QuollNet also cautions against treating core strength as universally convertible to corresponding standard-cured cylinder strength.[5]

Request the signed report at quotation stage. Ask who will sign it and what the sign-off covers. Make this an agreed deliverable, distinct from the project engineer’s interpretation, rather than assuming a particular signature or professional seal is required for every Ontario core report.

Before engineering interpretation, check report IDs against the location register and request clarification of missing or inconsistent entries. This preserves the connection between the result and sampled member that QuollNet recommends.[5]

Agree on interpretation—not online pass thresholds

Ask the engineer to specify the interpretation framework before sampling. QuollNet recommends defining this procedure in the investigation plan and separating measured results and corrections from the assessment or acceptance basis.[5]

The often-quoted ACI percentages have a specific context. In the three-core pathway described by QuollNet, average strength is at least 85% of specified strength, and no individual core is below 75%. These are acceptance thresholds within that pathway, not a core-to-cylinder conversion; the guide does not establish their applicability to a particular Ontario structure.[5]

Likewise, the ASTM length-to-diameter corrections described in the guide address specimen geometry under that method, not structural acceptance by themselves.[5] Ask the engineer which test method, corrections and acceptance provisions apply. QuollNet cautions against importing ACI thresholds into an EN/BS assessment unless the contract adopts that approach.[5]

Set fees, deadlines and reinstatement responsibilities

Soil-Mat’s cited laboratory-services page and Paterson’s cited concrete-testing page do not state fixed prices or turnaround times; Paterson offers a quote-request route.[3][4] Obtain a project-specific quote and schedule before authorizing work.

For each item, record the responsible party, charge or allowance, prerequisite and delivery date. Use these ordering prompts rather than assuming standard billing categories:

• Engineering planning: Confirm the fee, scope authorization and deadline for instructions to reach the contractor and laboratory.
• Locating and extraction: Confirm charges for locating embedded items, mobilization and extraction, plus access arrangements and the drilling date.
• Transport and laboratory work: Assign delivery, preparation, testing and reporting. Agree the processing period and report date.
• Engineering interpretation: Confirm its separate scope, fee and review date rather than assuming it is included in laboratory reporting.
• Hole reinstatement: Name who repairs each hole, when, at what charge and to whose detail. QuollNet recommends planning the repair method but does not prescribe an Ontario repair material.[5]

Ask how delays, unsuitable specimens, additional preparation or repeat attendance would affect charges and dates, and who authorizes extra work. Include delivery of the signed report and engineering interpretation in the schedule, not simply completion of drilling.

With the owner and engineer, identify access permissions and project-specific approvals needed before work proceeds. For renewal duties, ask whether an identified project requirement imposes recurring testing, report expiry or renewal; do not build these into the order by assumption.

Hand over the linked record for engineering interpretation

Before closing the order, resolve unmatched IDs, unexplained location changes, missing preparation or conditioning details, and undisclosed corrections with the contractor, laboratory and engineer. QuollNet links location identification, extraction records, preparation and testing as parts of a traceable investigation.[5]

Assemble the recommended handoff:

• Sampling and interpretation instructions: Agreed scope, represented members or regions, and assessment basis.[5]
• Marked location record: Drawings or coordinates connecting each ID to its member, elevation and drilling direction.[5]
• Core register and photographs: Matching IDs, extraction dates, orientation and observed defects.[5]
• Laboratory records and report: Dimensions, preparation, moisture conditioning, testing dates, maximum loads, strengths, test standard and corrections.[5] Include the agreed signed version.
• Reinstatement documentation: Request available records of repairs against the agreed hole-repair plan.

A core result is not clearance for the whole structure. Cores represent sampled areas; placement, consolidation and moisture history can contribute to variation within one member.[5] QuollNet describes further investigation, structural analysis, restrictions, strengthening, repair or replacement as possible responses to unsatisfactory findings, depending on the circumstances—not automatic demolition.[5] Send the linked package to the project engineer for interpretation and decisions about further work.

References

1. ONTARIO (on.ca)
2. Engineering & Construction Services Division Standard Specifications for (toronto.ca)
3. Soil-Mat | Materials Testing | Hamilton | Toronto (on.ca)
4. Laboratory Testing: Concrete – Paterson Group (patersongroup.ca)
5. Concrete Core Test Guide: ASTM C42, ACI 318-25 & BS EN 13791 (quollnet.com)