Background
Green Rise Foods Inc. operates a large commercial greenhouse tomato operation in Ontario. Its boilers serve dual purposes: heating the greenhouses and generating carbon-dioxide-enriched flue gas to accelerate photosynthesis. The flue gas inevitably contains carbon monoxide as a byproduct of combustion, and a Sercom Monitor was installed to alarm and vent unsafe CO levels before the gas entered the growing areas. In late February 2021, shortly after Green Rise purchased the operation, tomato plants began showing signs of damage. Investigation eventually revealed — not until March 17, 2021 — that a displaced internal burner diffuser had caused one boiler to emit excessive carbon monoxide, and that the Sercom Monitor had independently malfunctioned and failed to trigger any alarm. By the time the problem was discovered, 23 acres of tomato plants were lost.
Green Rise claimed the loss under a standard form greenhouse horticultural policy issued by the Dutch insurer N.V. Hagelunie. The insurer denied coverage on two bases: first, that the loss was caused by “exhaust gas,” which is categorically excluded under clause 11 of the policy; second, that the boiler and monitor malfunctions constituted “machinery breakdown,” which is both an exception carved out of the initial grant of standard property coverage and a separate stand-alone exclusion. The insurer’s denial letter added, without inspecting the equipment or requesting maintenance records, that the machinery breakdown was attributable to lack of maintenance.
Green Rise commenced an action for breach of contract and moved for partial summary judgment seeking a declaration of coverage. The motion judge upheld the insurer’s denial. He found the exhaust gas exclusion unambiguous and dispositive, and alternatively found that the machinery breakdown exception to the initial grant of coverage independently defeated the claim. He granted boomerang summary judgment dismissing the action entirely and awarded the insurer costs of $157,377.37.
The Court’s Holding
The Court of Appeal allowed the appeal and remitted the entire action for trial. Writing for a unanimous three-judge panel, Roberts J.A. identified two independent legal errors in the motion judge’s analysis. First, the motion judge committed a causation error: although he correctly found that the loss resulted from a series of events — a malfunctioning boiler, a malfunctioning monitor, and resulting CO emissions — he then collapsed the analysis by treating only the most immediate-in-time event (carbon monoxide poisoning of the plants) as the operative cause for coverage purposes. Under settled Canadian insurance law, “proximate” cause means the cause that is proximate in efficiency (the effective cause), not the cause nearest in time. The motion judge was required to determine whether the loss arose from a single effective cause within a chain of causation or from concurrent causes — a determination that could not be made without analyzing the causes of the boiler and monitor malfunctions themselves.
Second, the motion judge erred in his alternative machinery breakdown analysis by failing to address who bore the onus of proof with respect to the machinery breakdown exception in the initial grant of coverage, and by making no factual findings about why the boiler and monitor actually malfunctioned. These omissions precluded any proper legal conclusion about whether the exception applied. Because there was competing evidence on the factual causes of the malfunctions and because the effective cause of the loss had never been properly determined, the Court of Appeal declined to decide those questions itself and held that genuine issues requiring a trial existed on the full record.
For the guidance of the trial judge, the court set out the correct analytical sequence: (i) determine the effective cause or causes of the loss using chain-of-causation or concurrent-cause principles; (ii) assess whether the initial grant of coverage is met (with the insured bearing the onus); (iii) assess whether the insurer can establish that an exclusion applies; and (iv) assess whether the insured can establish any exception to an exclusion. The trial court will need to revisit the exhaust gas exclusion and the machinery breakdown provisions with these principles in mind.
Key Takeaways
- In insurance coverage disputes involving a series of events, courts must identify the effective cause of the loss — not simply the cause closest in time. Focusing on the immediate-in-time event without considering what was in substance the efficient cause is a reversible error of law.
- Where a policy’s initial grant of coverage contains an exception (here, machinery breakdown), the court must explicitly address who bears the onus of proof on that exception before deciding whether it applies.
- Boomerang summary judgment is inappropriate where competing factual evidence exists about the causes of a claimed loss and the motion judge’s causation analysis was legally flawed; those are genuine issues requiring a trial.
- The correctness standard of appellate review applies to interpretation of standard form insurance policies, meaning no deference is owed to the motion judge’s reading of the policy language: Ledcor Construction Ltd. v. Northbridge Indemnity Insurance Co., 2016 SCC 37; Emond v. Trillium Mutual Insurance Co., 2026 SCC 3.
Why It Matters
This decision reinforces the analytical rigour required in multi-event insurance coverage disputes. Insurers and policyholders alike must approach causation systematically — identifying whether events form a single chain with one efficient cause or constitute truly concurrent independent causes — before reaching for coverage grants, exceptions, or exclusions. A shortcut to the most recent event in the chain is not just analytically incomplete; it is a reviewable legal error.
For the greenhouse and agri-business insurance market specifically, the decision highlights the hazard of denying claims based solely on the proximate-in-time mechanism of crop damage (here, toxic gas) while ignoring the upstream equipment failures that set that mechanism in motion. Whether the insurer’s machinery breakdown exception or exhaust gas exclusion ultimately prevails will depend on facts that require a full trial — a costly reminder that summary disposition of complex multi-cause insurance disputes carries significant appellate risk.