Is structural field review required in Ontario?

Yes. The Ontario Building Code (Division C, Part 1) requires General Review of construction by the design professionals of record for Part 3 buildings and for many Schedule 1 building types. For structural elements designed under OBC Part 4, general review (field review) is required unless expressly waived by the building official, which is rare for significant structural work. PEO's practice guidelines treat structural field review as a professional obligation for any engineer who seals structural drawings — the engineer's professional duty extends beyond producing drawings to confirming construction conforms.

What do structural shop drawings contain?

Structural shop drawings are prepared by the fabricator or contractor and show the detailed fabrication and erection information needed to construct the structural elements designed by the engineer. For structural steel, shop drawings show: member profiles, lengths, and weights; connection details and bolt patterns; base plate and anchor bolt layout; weld sizes and symbols; and camber and finish requirements. For reinforced concrete, placing drawings show: rebar sizes, shapes, lap lengths, spacing, and cover dimensions; bar schedules; and embed plate details. The engineer reviews shop drawings to confirm they conform to the design intent of the sealed structural drawings.

What is a Request for Information (RFI) on a construction project?

An RFI (Request for Information) is a formal written request from the contractor to the design team (architect, structural engineer, mechanical engineer) seeking clarification of the contract documents — drawings, specifications, details, or requirements. RFIs are an essential part of the CA process: they identify gaps or ambiguities in the construction documents, allow the engineer to confirm design intent or issue a clarification, and create a documented record of design decisions made during construction. Unresolved RFIs or slow RFI responses are a significant source of construction delay and claims in Ontario projects.

What happens if the contractor builds something different from the engineer's drawings?

If a contractor constructs structural work that deviates from the sealed drawings, the structural engineer has a professional obligation to: document the non-conformance in a field review report; notify the contractor and owner in writing; assess whether the as-built condition meets structural requirements; and direct remedial action if the non-conformance is structurally significant. In Ontario, the engineer cannot issue a final General Review Certificate if substantial non-conformances exist that affect structural adequacy. The engineer's refusal to certify can trigger significant contract disputes — but certifying work that does not conform could expose the engineer to professional liability.

Construction Administration for Ontario Structural Projects

Q: What is structural field review in Ontario?

Structural field review (SFR) is the on-site engineering activity where the engineer of record (or their designated P.Eng. or intern engineer) visits the construction site to verify that the structural work being performed conforms to the sealed structural drawings and specifications. PEO's 'Guidelines for Professional Engineers Providing Structural Field Review' (2019) sets out the minimum requirements: the engineer must visit the site at defined stages, document observations in field review reports, and confirm in writing at the end of construction that the structural work conforms (or note non-conformances) in a final General Review Certificate submitted to the building department.

Construction Services| 9 min read|April 2026 · By Asvakas Engineering

What Is Construction Administration?

Construction administration (CA) is the suite of engineering services that span from construction start to occupancy — distinct from the design phase but equally important to project success and structural safety. While design work produces the drawings and specifications, CA ensures that the constructed building actually matches the engineer's design intent and complies with the Ontario Building Code.

For structural engineers in Ontario, CA encompasses four core activities: (1) structural field review — on-site observations during defined construction stages; (2) shop drawing review — reviewing fabrication drawings for conformance with the structural design; (3) RFI response — answering contractor questions about structural details; and (4) change order support — assessing the structural implications of requested changes to work in progress. Each activity is governed by both professional obligations (PEO guidelines) and contractual obligations (the OBC and the construction contract).

Structural Field Review in Ontario

Field review is the most critical and liability-laden component of structural CA in Ontario. PEO's Guideline for Professional Engineers Providing Structural Field Review (2019 edition) defines minimum requirements and professional obligations for Ontario engineers.

Why Field Review Is Required

The professional engineer's seal on construction drawings is a representation that the design meets code requirements — but it cannot guarantee that the contractor built it correctly. Field review closes this gap. The OBC (Division C, Part 1) mandates General Review by design professionals for Part 3 buildings and for prescribed Schedule 1 projects. General Review means that the engineer must visit the site at defined stages, document observations, and certify (or qualify) conformance at each stage and at project completion.

Required Field Review Stages for Structural Work

PEO's guidelines identify the minimum field review visits for typical structural systems:

Foundation: Prior to concrete placement — inspect excavation dimensions and bearing conditions, verify bearing soil matches geotechnical assumptions, confirm rebar installation matches drawings.
Grade beams & slabs-on-grade: Confirm sub-base, vapour barrier, and rebar before concrete placement.
Structural steel: During erection — confirm member sizing, connection bolts/welds, base plates, bracings, and temporary stability provisions. After erection and prior to concrete placement on composite decks.
Concrete suspended slabs and beams: Confirm rebar, embed plates, and pre-stressing tendons before placement. Confirm post-tensioning stressing after placement.
Shoring and formwork (if designed by the structural engineer): Confirm installation conforms to sealed shoring drawings before excavation or loading.
Final structural review: Before the Occupancy Permit, confirm all outstanding structural non-conformances have been resolved.

Field Review Reports

Each site visit must be documented in a written field review report issued to the contractor and owner within a reasonable time after the visit. The report must describe what was observed, what was found to conform, what non-conformances were identified, and any instructions given to the contractor. Field review reports are discoverable in litigation and are routinely produced in Ontario construction disputes — accurate, contemporaneous documentation is essential.

Shop Drawing Review

Shop drawings are prepared by fabricators and specialty contractors to show exactly how they intend to fabricate and install the structural elements designed by the engineer. The engineer's review confirms that the shop drawings conform to the design intent of the sealed structural drawings.

Structural Steel Shop Drawings

Steel fabrication drawings show: member identification, profile size (W310×97 etc.), length and cut, end preparation, connection details (bolts, welds, gusset plates), base plates and anchor bolt layout, camber directions, CISC/CWB certification, paint or primer system. The engineer reviews for: correct member sizes matching structural drawings, connection design matching the engineer's connection specifications (bolt type, grade, and pattern; weld size and type), anchor bolt layout integrity, and appropriate material grades.

Concrete Reinforcing Shop Drawings (Placing Drawings)

Placing drawings (prepared by the rebar subcontractor) show rebar sizes, bend shapes, lap lengths, spacing, cover, support chairs, and bar schedules for each pour area. The engineer reviews for conformance with the structural drawings and CSA A23.1 placing requirements, including minimum cover for the specified exposure category (exposure class), development length compliance, and lap locations per the engineer's splice diagram.

Review Turnaround Obligations

Construction contracts typically specify a shop drawing review turnaround of 10–15 business days. PEO's guidelines acknowledge that timely review is a professional obligation — unreasonably delayed responses expose the engineer to professional and contractual liability for delay damages. For projects with tight schedules, the engineer should agree with the contractor on a submittal schedule and review priority list at the project kickoff meeting.

The RFI Process

A Request for Information (RFI) is a formal contractor inquiry seeking clarification about the design documents. Structural RFIs are typically about: conflicting or unclear dimensions between architectural and structural drawings; reinforcing details not shown for a specific condition; structural implications of a proposed substitution; or questions about construction methods (e.g., "can we install this column base plate on dry-pack mortar instead of non-shrink grout?").

The Engineer's Response

The engineer's RFI response must be technically sound, timely (within the contractually specified period, or if not specified, within a reasonable time), and clearly stated. Response options include: Answer/Clarify (no change to drawings), Issue Supplemental Drawing (a sketch or clarification drawing attached to the RFI), Direct to Change Order (if the contractor's request changes design intent in a way that affects cost or time), or Return for Resubmission (if the RFI is unclear or lacks sufficient information).

RFI records are critical in Ontario construction claims and arbitration. A well-managed RFI log — tracking submission date, engineer response date, and disposition — demonstrates that the engineering team was responsive and professional. Contractors who claim delay due to slow RFI responses must show that the RFI was on a critical path activity and that the response was unreasonably delayed.

Non-Conformances & Change Orders

Identifying Non-Conformances

A non-conformance is any structural work that does not match the sealed drawings or specifications. Common non-conformances on Ontario structural projects include: incorrect rebar size or spacing; missing structural embedding or anchor bolts; undersized or incorrectly located structural steel members; insufficient concrete cover (exposed later by inspections or GPR scanning); inadequate weld quality (identified by NDT — ultrasonic or magnetic particle testing); and unauthorized structural modifications made without engineering direction.

Engineer's Response to Non-Conformances

When a structural non-conformance is identified, the engineer must: document it in the field review report; assess its structural significance (is it a minor deviation or a safety-critical deficiency?); communicate the required corrective action to the contractor in writing; and follow up at the next site visit to confirm correction. For minor deviations, the engineer may accept the as-built condition with or without supplemental reinforcement — but this must be documented clearly.

Construction Closeout & OBC Certification

At the conclusion of structural work, the engineer issues a General Review Certificate (Schedule 2 under OBC Division C) confirming that, to the best of their knowledge, the structural work conforms to the sealed drawings and the OBC. This certificate is a condition for the building department to issue an Occupancy Permit.

The certificate states the extent of review — it does not certify that every square metre of rebar was personally inspected. If the engineer was not retained for full field review, the certificate must be qualified to reflect the actual scope of review performed. Issuing an unqualified certificate for work the engineer did not actually review is a professional misconduct risk under the PEO Code of Ethics.

Outstanding non-conformances must be resolved before the engineer can issue an unqualified General Review Certificate. If minor outstanding items remain at occupancy, the engineer may issue a conditional certificate with an explicit list of outstanding items and a commitment to a final certificate after resolution.

Frequently Asked Questions

Is structural field review required by law in Ontario?

Yes. The OBC requires General Review for Part 3 buildings and prescribed building types. PEO's guidelines treat structural field review as a professional obligation for any engineer who seals structural drawings. The engineer's professional duty extends from design through construction to final certification.

What are shop drawings?

Shop drawings are detailed fabrication drawings prepared by the contractor or fabricator (for steel, rebar, precast, etc.) showing how structural elements will be built. The engineer reviews them to confirm they match the design intent of the sealed structural drawings — they don't constitute a new design by the engineer.

What is the engineer's stamp on a shop drawing review?

The engineer's review stamp on a shop drawing means the engineer has reviewed the drawing for conformance with the structural design intent. It does NOT mean the engineer has designed the fabrication details, nor that every item shown is correct — fabricators retain responsibility for their own fabrication quality. The engineer's review is not a substitute for the contractor's own quality control.

How often should the structural engineer visit the site?

PEO's guidelines define minimum required visits by construction stage (foundation, framing, etc.) — the engineer must visit before concrete is placed in foundations and slabs, during steel erection, and at other critical stages. For complex projects, visits are more frequent. The frequency must be sufficient for the engineer to certify conformance at each stage.

Can I skip CA to save money on a renovation project?

For OBC Part 9 (small residential) renovations, limited CA may be acceptable. For Part 3 buildings and any project under OBC General Review requirements, CA is mandatory. Even where not legally required, skipping CA increases the risk of undetected structural non-conformances that can cause long-term performance problems and create professional liability issues for the engineer of record.

Construction Administration Services in Ontario

Asvakas Engineering provides full structural field review, shop drawing review, RFI response, and OBC General Review Certificates for construction projects across Toronto and Ontario.

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