Notice and time bars in Ontario

This page is about the law of Ontario notice: why the rule is as hard as it is, where it stops, and what remains when it has been missed. It does not repeat the deadlines: every contractual, statutory and lien clock that can kill an Ontario delay claim, with its trigger and its character in law, sits on the companion page of Ontario delay claim clocks. Read that for the numbers and this for the reasoning.

Two orientation points before the doctrine. First, Ontario is a common-law province, so the general Canadian position at the Canada extension-of-time hub is the backdrop and Ontario supplies most of the leading cases. Quebec is civil law and is carved out entirely: nothing on this page governs a Quebec contract, and Quebec notice and time bars is a separate regime. Second, an evidence warning that applies to every citation here: CanLII, the Supreme Court portal, ontariocourts.ca and Ontario e-Laws all blocked automated fetching for this corpus, so no Canadian judgment and no Ontario statutory text was read from an official consolidated source. Every case and section number below rests on independent secondary sources and must be checked by a human or an authenticated tool before it is put in a pleading.

Ontario treats a notice-of-claim period as a condition precedent, and prejudice is irrelevant

A contractual provision requiring written notice of a claim within a stated period is enforced in Ontario as a condition precedent to maintaining the claim in court. Non-compliance forfeits the entitlement itself, not merely a procedural step, and the owner is not required to prove that the late or absent notice caused it any prejudice. That is Technicore Underground Inc v Toronto (City) 2012 ONCA 597, and it is the single most consequential proposition in Ontario delay practice.

Two features make the Canadian rule harder than the English one a practitioner may be carrying. The clause does not need to say what happens if it is breached: Corpex (1977) Inc v The Queen in right of Canada 1982 CanLII 213 (SCC) holds that a notice provision can bar a claim even without express "failing which" language. And the owner's actual awareness of the delay does not substitute for the notice: Technicore disposes of the prejudice argument, and Northland Kaska Corp v R 2001 BCSC 929 supplies the line that "the grumblings of a contractor are not sufficient to constitute notice."

"Strict compliance" in practice has meant three things. The notice must be in the form the contract specifies, sent to the person the contract names, not to whoever happened to be in the site meeting. It must be within the window the contract fixes, measured from the trigger the contract fixes, and under CCDC 2 – 2020 GC 6.5.4 that trigger is the commencement of the delay, not the contractor's awareness of it, which means a contractor can be time-barred before it knew there was anything to notify. And it must be a notice of claim, not a report: a monthly progress report, a schedule update or a meeting minute recorded by someone else is not notice, and the failure is almost never ignorance of the clause but a contract administrator who believed the routine reporting was doing the work. Note also that under the CCA 1 – 2021 subcontract the time-notice period is 7 Working Days: three fewer than the CCDC 2 main contract, on the same project and often on the same facts.

What Elite decided, and why summary judgment is the litigation risk

Elite Construction Inc v Canada (Attorney General) 2021 ONSC 562 dismissed a CAD 4.1M delay and extras claim on summary judgment, on a contract requiring "written notice of any intention to claim additional compensation or damages within ten working days of the date the neglect or delay first occurred." The decision was affirmed on appeal. The Court of Appeal upheld the dismissal and confirmed that compliance with a notice provision is a condition precedent to maintaining a claim in the courts. The appellate neutral citation, reported as 2021 ONCA 803, is unverified in this corpus: it comes from a decision digest, not the judgment, and should be checked before it is cited.

The part most often missed is the appeal. Elite is frequently described as a first-instance summary-judgment outcome, which invites the reply that a trial judge might have taken a softer view. The Court of Appeal's affirmation removes that reply.

What matters strategically is the procedural route. Because notice compliance is a condition precedent, it is a discrete question that can usually be answered on a documentary record without findings about causation, critical path or quantum, which makes it ideally suited to summary disposition, and Ontario courts have shown a real appetite to dispose of eight-figure delay claims that way. Sufficiency of a claim submission has been decided the same way, on an application. The consequence for a contractor is that the notice file will be read cold, by a judge, in a motion record, without a witness to explain it, usually years after the events and without the benefit of the project context that made the correspondence intelligible at the time.

The contrast is instructive. Where the notice gate is passed, an Ontario delay claim can become enormous: Walsh Construction v Toronto Transit Commission 2024 ONSC 2782 was a CAD 165.925M contract tried over 161 days. In Ontario a large delay claim is decided at the gate or it is decided at extraordinary length, and there is very little in between. Budgeting a delay claim without pricing the gate motion misprices the risk.

Sufficiency: an inadequate claim is not a late claim, it is a non-existent claim

Timing is only half of the Ontario rule. A claim submission must contain sufficient particulars, and insufficiency extinguishes the right to claim in exactly the same way lateness does. In Ross-Clair v Canada (Attorney General) 2016 ONCA 205, (2016) 347 OAC 177, the contractor submitted a claim for extras of $1,437,976 and the owner disputed the sufficiency of the supporting information. The Court of Appeal held that the contractor must in substance prove its claim to the other side in the submission itself, and treated sufficiency as a threshold requirement.

Failure to provide sufficient information within 30 days after completion is a failure to provide notice of the claim at all.

That is the sentence to carry, and its structure is what makes it dangerous. An inadequate claim is not a late claim. It is a non-existent claim. There is no partial credit, no discount for a claim that was nearly particularised, and no scope for the argument that the owner could have asked for more. The standard of review on appeal was correctness, the contract being a standard-form government contract. (The general condition number of the clause construed is unverified in this corpus.)

So what does a sufficient Ontario notice actually contain? Working from what Ross-Clair required, three things have to be inside the notice window, not supplied later:

1. The causation narrative. What the event was, when it began, who is responsible for it under the contract, and the mechanism by which it delayed the work. A bare assertion that the owner "caused delay" is a placeholder, not a narrative.
2. The schedule impact. Which activities were affected, and the effect on the completion date or the Contract Time: expressed as a claimed period, not as a reservation of rights to quantify later.
3. The quantum basis. Not a fully proved account, but the heads of cost claimed and the basis on which they are calculated, sufficient for the owner to understand and test the money being sought.

Two administrative corollaries. Where a notice must be given "not later than 10 Working Days after the commencement of the delay" under CCDC 2 – 2020 GC 6.5.4, the drafting of the notice cannot wait for the impact to be measured. The entitlement narrative and the best available impact assessment must go in on time, with the detail following. And one notice suffices for a genuinely continuing cause of delay under GC 6.5.4, but a new cause needs a new notice. The most common failure mode is a contractor treating an early notice as an umbrella over events that are in truth separate.

The limit of the rule: a staged-ADR period is a minimum, not a cut-off

Ontario does not read every "within X days" in a construction contract as a time bar, and the distinction is genuinely useful. In J.P. Thomson Architects Ltd v Greater Essex County District School Board 2025 ONCA 378, an architectural services contract with a school board provided at GC 18 that any dispute "which cannot be resolved by the parties within thirty (30) days of the dispute arising, shall be referred to mediation, upon the request of either party." The Board read that as a 30-day deadline to demand mediation and refused mediation sought 15 months later.

The Court of Appeal reversed the court below. The 30-day period is a minimum period in which the parties must attempt resolution before initiating mediation, not a cut-off. Rigid time limits would undermine dispute resolution and conflict with sound commercial principles, particularly in ongoing professional relationships where issues evolve gradually.

Layer: jurisdictional. Both readings rest on Court of Appeal for Ontario authority: Technicore, Elite and Ross-Clair on the left, J.P. Thomson on the right. The rows rest on secondary sources and no judgment was read in original form.

The practical instruction is short: before conceding a deadline, ask which of the two kinds of clause you are looking at. Ontario public-works forms in particular chain both types together, and the staged ADR clocks in them are not bars.

Read the supplementary conditions before the general conditions

Across Canada, supplementary conditions almost universally amend CCDC 2 GC 6.5, and the amendments usually tighten the notice regime rather than loosen it. The Ontario exception is the one that surprises people. The OAA/OGCA Agreed-to Recommended Supplementary Conditions for CCDC 2-2020: current version 15 March 2024, R00, issued with OAA Practice Tip PT.23.11: contain no supplementary condition amending GC 6.5 at all. The 10 Working Days notice, the causes of delay and the delay-cost recovery stand unamended in the leading Ontario negotiated package. That is a recorded negative finding, and it is the useful kind.

The package does touch the neighbouring provisions, and two of the amendments change how a delay claim is run:

• SC 6.6.1 adds "and the Consultant" to the recipients of the money notice. On an OAA/OGCA-supplemented CCDC 2 – 2020, the GC 6.6.1 notice of intention to claim a change in the Contract Price must go to the Consultant as well as the Owner. A contractor who notices only the Owner has not complied: a trap made worse by the fact that GC 6.6.1 itself sets no fixed period, only a requirement that the notice be "timely", so there is no deadline to prompt a second look at the addressee.
• SC 8.3.9 to 8.3.13 let the Consultant join the arbitration as a full party, within 10 days of receipt and on 5 days' notice, where the financial-interest criteria in 8.3.10 are met. A two-party delay arbitration can therefore become tripartite at the Consultant's election, so the design-delay and construction-delay allegations get tried together. There is no CCDC-standard analogue, and it changes how a contractor should plead a claim that blames late instructions.

The significance of the untouched GC 6.5 is what it implies about where Ontario risk actually gets reallocated. The two bodies that negotiate the Ontario market standard left the delay clause alone. Delay risk in Ontario is therefore reshaped in owner-drafted supplementary conditions (no-damage-for-delay clauses, and contractual limitation periods shortened under the Limitations Act, 2002) not in the industry-agreed package. Public boards and institutional owners publish their own supplementary conditions, and those are the documents that move the deadlines. Always read the supplementary conditions before the general conditions, and read them looking for two things: an amendment to the notice machinery, and a contractual limitation clause.

The public-works forms are the real trap

A practitioner arriving from CCDC will find none of the familiar clause numbers and none of the familiar deadlines in Ontario's government standard form. The OPSS General Conditions of Contract run their own self-contained claim procedure, and they come in two families whose clause numbers do not correspond: OPSS.MUNI 100 (municipal, November 2019) and OPSS.PROV 100 (MTO, provincial highways, April 2023, with a July 2025 draft out for consultation and a live amendment notice to the April 2023 edition). Cite the family and the edition, every time.

Three features catch people out.

Second, the verbal notice step. OPSS.MUNI 100 GC 3.13.03 requires verbal notice immediately on becoming aware of a potential claim situation, followed by a written Notice of Intent to Claim within 7 Days of the commencement of any part of the Work affected, followed by a detailed claim no later than 30 Days after completion of the work affected, extendable to 90 Days with written approval. The immediate verbal notice is a separate obligation and it is the step people skip, and because it is verbal, the only evidence it happened is a contemporaneous record made by the contractor.

Third, the prescribed form. OPSS.PROV 100 GC 3.06 requires an application for an extension of Contract Time to be made in writing on MTO form PH-CC-756, Compensation Request, to the Contract Administrator, "as soon as the need for such extension becomes evident". Two traps in one clause: a contractor that writes a letter has not made an application, and a contractor waiting for the impact to crystallise has waited too long. There is no day count to diarise, which is precisely why the deadline is missed.

Read the two families together and the Ontario public-works pattern is a staged condition precedent: verbal notice, then written notice of intent, then the detailed claim, then the Contract Administrator's opinion, then negotiation, then mediation, then arbitration, each with its own clock. The notice steps are conditions precedent. The staged ADR periods that follow are minimums, not cut-offs, on the J.P. Thomson reasoning. Do not concede the second kind because the first kind is strict.

On an IO project agreement, the notice periods are project-specific, read the agreement

An Infrastructure Ontario Project Agreement does not have a delay clause in the CCDC sense. It splits the territory three ways, and the classification of the event, not its factual severity, determines the remedy. A Delay Event (an event other than a Compensation Event, Relief Event or Force Majeure that delays completion) gives time only, an extension of the Scheduled Substantial Completion Date. A Compensation Event gives time and money, by adjustment to the Guaranteed Price. A Relief Event gives neither, only relief from performance and from default remedies. There is no CCDC analogue to a Relief Event: an event can be real, disruptive and entirely outside Project Co's control and produce neither an extension nor a dollar. An express mitigation obligation attaches to each of the three, and it is a condition of the relief rather than an implied duty to be argued about. Do not carry Article numbers between projects. The classification is stable. The numbering is not.

The notice day counts were not surfaced in this corpus and they are project-specific. The tripartite Delay Event / Compensation Event / Relief Event architecture is real, but the Article numbers are not fixed across IO projects: in one published agreement Articles 31 to 33 are Variations, Delay Events and Compensation Events. In another they are Payment, Taxes and the Financial Model. Read the numbering off the agreement in front of you. The periods are not surfaced either. They sit partly in the Articles and partly in the Schedules, and they vary between projects. Infrastructure Ontario publishes redacted execution-version Project Agreements with schedules, and the New Toronto Courthouse and Mount Sinai Hospital Redevelopment Phase 3A agreements are the fullest public sources. That is a materially better research posture than most jurisdictions offer. An Ontario practitioner can read the actual governing template rather than a commentary on it. Never assume an IO notice period from CCDC, and never assume it from another IO project.

On how those provisions are enforced, Crosslinx Transit Solutions Constructors v Ontario Infrastructure and Lands Corporation 2021 ONSC 3567 (the Eglinton Crosstown LRT) held that COVID-19 was an "Emergency" within the Schedule 1 definition, that the Authority required compliance with the Construction Protocols, and that those protocols were "additional or overriding procedures" under section 62.1 rather than Applicable Laws, so Project Co could pursue a Variation claim for an extension of the Substantial Completion Date. The transferable drafting point is that the Force Majeure clause was a closed list that did not include pandemics, and the claim succeeded through a different route entirely. On appeal, reported as 2022 ONCA 187, the holding was that notice means actual notice: an internal email of 25 March 2020 could not constitute notice because it was never communicated to the contractor, and the analysis "must start with the notice provision itself." That appellate citation, and its precise relationship to the 2021 first-instance decision, were taken from a firm bulletin rather than the judgment, and are unverified.

Two structural points close this section. These are the only substantial reported Ontario judgments interpreting an IO Project Agreement's time-relief machinery, and both turn on characterisation and notice, not on delay analysis: IO delay claims in Ontario are won on contract construction, not on windows analysis. And no public judgment or published award on Ontario Line delay exists: IO and Metrolinx project agreements resolve confidentially, so Ontario's largest transit delay disputes generate no citable law. That is a structural fact about the jurisdiction, not a gap in searching.

What survives a missed notice, and how little it is

Very little, and none of it is reliable. The Ontario escape routes are fact-heavy, and each of them typically produces a triable issue rather than a win, which on a summary-judgment motion is worth having, but is not the same as an entitlement.

Waiver by conduct is the main exception and the strongest. Colautti Construction Ltd v Ottawa (City) 1984 CanLII 1969 (ONCA) is the Canadian anchor: the owner had repeatedly paid for unauthorised extras, and could not then insist on the formality it had consistently ignored. Its requirements are demanding: a course of conduct inconsistent with reliance on the bar, not a single indulgence, and conduct by someone with authority to bind the owner. Note the related gap: there is no Canadian appellate decision on the ostensible authority of a CCDC Consultant to bind an Owner to an extra, so Colautti waiver-by-conduct is the argument to plead rather than an authority argument about the Consultant.

Actual knowledge is weak on its own. Technicore removes prejudice from the analysis, Northland Kaska disposes of informal grumbling, and Crosslinx on appeal confirms that an internal email circulating inside the owner's own organisation is not notice to the other party, because it was never communicated to it. Contemporaneous records (emails, meeting notes, schedule updates) can do evidential work, but they do it best in support of a waiver or estoppel case, not as a substitute for the notice.

Good faith is the distinctively Canadian argument and it does something different from what contractors hope. Bhasin v Hrynew 2014 SCC 71 and C.M. Callow Inc v Zollinger 2020 SCC 45 establish the duty of honest performance, and Wastech Services Ltd v Greater Vancouver Sewerage and Drainage District 2021 SCC 7 requires a contractual discretion to be exercised reasonably and consistently with the purpose for which it was conferred. An owner administering an extension-of-time clause is exercising exactly such a discretion, so bad-faith refusal of an extension founds a distinct claim, a cause of action with no English equivalent. But it repairs nothing. It gives a contractor a claim about the owner's conduct in handling a notice that was given. It does not manufacture a notice that was not. And the Wastech argument has not yet been run in a reported Canadian delay case. It is structurally sound and untested.

Two further points a reader should not have to discover the hard way. Adjudication does not rescue a late claim. Under the Construction Act and O. Reg. 264/25 s 19, a request for an extension of time to complete the work became adjudicable in Ontario on 1 January 2026, but only as an ancillary head where resolving it is "reasonably necessary" to a subsequent determination, only on contracts entered on or after that date, and not on public-private-partnership projects, and adjudication is a payment regime that does not reopen a contractual notice bar in any event. (A minor conflict exists on the provision number: one firm refers to s 19.1 while ODACC, the OAA and Cassels refer to s 19. Prefer s 19.)

And the prevention argument is unresolved in Ontario. Whether an owner's own delay puts time at large despite a failed condition-precedent notice (the Gaymark question) is answered firmly no in England, in Multiplex Constructions (UK) Ltd v Honeywell Control Systems Ltd (No 2) [2007] EWHC 447 (TCC). No Ontario authority on the prevention principle or on time at large was located at all. The question is genuinely open in Ontario, and it is available as an argument rather than as a rule. How the argument is framed in the abstract is set out on the neutral notice and time bars page.

The notice clock and the limitation clock are different clocks

A valid notice does not stop the limitation clock, and nothing in a contractual claims procedure suspends the statutory period. The two operate independently and a contractor can comply perfectly with one while the other expires. Under the Limitations Act, 2002, s 4 gives a basic period of two years from discovery, applying the four-limb s 5 test, which includes the awkward limb asking whether "a proceeding would be an appropriate means" to remedy the loss, with a 15-year ultimate period under s 15.

The Ontario-specific point is what the contract may have done to that period. Under s 22(5)–(6), in a business agreement (one in which none of the parties is a consumer, which a construction contract between commercial parties almost always is) a limitation period may be varied or excluded, and "vary" expressly includes extend, shorten and suspend. Ontario is the only Canadian jurisdiction where commercial parties may lawfully shorten or exclude a limitation period. Alberta, Saskatchewan and Manitoba permit extension only. In Quebec, art 2884 C.c.Q. permits nothing at all, so the identical clause in a Quebec contract is a nullity. An Ontario owner's supplementary conditions can therefore impose a bar substantially shorter than two years on all delay claims, and it will bind.

It must, however, be drafted properly. Ontario (Transportation) v J & P Leveque Bros Haulage Ltd 2025 ONCA 573 sets a three-part test: the clause must use clear language describing a limitation period, identify the scope of its application, and exclude the operation of the statutory periods. The Ministry of Transportation's own clause, on a Highway 60 rehabilitation contract, failed it, so the statutory s 4 period governed and the action was not barred. If the province's standard form cannot get a contractual limitation clause right, an owner's bespoke supplementary conditions are unlikely to, and a defective clause leaves the statutory default standing, which is usually what the contractor wants.

The working sequence in an Ontario delay file therefore runs: read the supplementary conditions for the notice machinery and for a contractual limitation clause, diarise the notice period from the contractual trigger, not from awareness, give a notice that carries causation, schedule impact and quantum basis inside the window, and diarise the limitation period separately, against whatever the contract has made it. The statutory clock, accrual and the Leveque test are worked through on limitation periods and claim accrual in Ontario. The wider Ontario picture, including which of the three date-keyed regimes a contract falls into, is at the Ontario extension-of-time hub.

À propos de ce contenu Le contenu de la bibliothèque est une information générale sur la pratique des réclamations de construction, et non un avis juridique. Le droit à réclamation, les délais et la procédure sont régis par votre propre contrat et par le droit du lieu où les travaux sont exécutés. Révisé le 8 août 2026 · Signaler une correction