When a fire starts in a commercial kitchen exhaust system, the physical damage is often obvious. What is less visible, but frequently more costly, is what happens afterwards, when insurers begin their investigation.
Kitchen exhaust fires are well understood by insurers. They are common, foreseeable, and closely scrutinised. As a result, insurers often approach these claims with an implicit assumption: if a fire occurred in the exhaust system, the risk may not have been adequately managed. From there, the burden shifts to the insured to prove otherwise.
How Insurers Investigate Kitchen Exhaust Fires
When assessing a kitchen exhaust fire, insurers quickly move beyond the ignition point. Their investigation typically focuses on:
- Whether the exhaust system was cleaned and maintained
- How often cleaning occurred and to what standard
- Whether grease accumulation was monitored or controlled
- Who was responsible for arranging maintenance
- Whether maintenance aligned with applicable standards
- What records exist to prove the system was properly managed
This is where the concept of de-facto proof emerges. In practice, insurers often treat the existence of an exhaust fire as an indicator that controls may have failed, unless there is clear evidence to the contrary.
In other words, the fire itself becomes a trigger for heightened scrutiny, not a neutral starting point.
Fire as Evidence of Inadequate Risk Control
Most commercial insurance policies require insured parties to take reasonable precautions to prevent loss and to comply with applicable laws and standards. Kitchen exhaust fires are a known and foreseeable risk. Grease accumulation, ignition, and flame spread through ductwork are not unexpected events. Because of this, insurers frequently assess these claims on the basis that:
If appropriate controls were in place, the fire should not have occurred, or should have been contained.
This does not mean insurers automatically deny claims. But it does mean the insured must be able to demonstrate that:
- The risk was recognised
- Appropriate controls were in place
- Those controls were implemented consistently
- Records exist to prove this
Where that evidence is weak or inconsistent, insurers may argue that reasonable precautions were not taken.
Why Lease Silence Doesn’t Protect Anyone
One of the most common failure points in kitchen exhaust fire claims is the lease. Many leases are silent on exhaust maintenance or refer only vaguely to keeping premises in “good order.” This creates a dangerous gap where landlords may assume tenants are managing exhaust cleaning and tenants may assume landlords are responsible for building systems. From an insurer’s perspective, this ambiguity is rarely helpful to either party.
Insurers are not bound by the landlord-tenant relationship. Their focus is whether the insured; landlord; tenant, or both, took reasonable steps to manage a known fire risk. If responsibilities were unclear and maintenance records are missing, insurers may argue that the risk was not properly controlled by anyone. In short, lease silence doesn’t shift responsibility, it multiplies exposure.
Where Claims Typically Unravel
Kitchen exhaust fire claims tend to unravel in predictable ways:
-
Incomplete or poor-quality records
Invoices without scope, missing dates, or cleaning reports that don’t align with claimed frequencies raise immediate concerns.
-
No recognised maintenance framework
If cleaning occurred “as needed” without reference to AS 1851 or a recognised best-practice framework, insurers may argue the approach was informal and inadequate.
-
Disputes over responsibility
When landlords and tenants disagree about who was responsible, insurers may delay settlement, reduce payouts, or seek recovery after payment.
-
Failure to control grease accumulation
Even where cleaning occurred, insurers may focus on whether grease build-up was properly managed, not just whether a contractor attended.
In some cases, insurers will still pay third-party claims (such as damage to neighbouring properties) but then pursue recovery from the party they believe failed to manage the risk.
Compliance Alone Is Not Enough
From February 2026 in NSW, some kitchen exhaust systems will be required to comply with AS 1851-2012, where they are listed as prescribed fire safety installations.
AS 1851 provides a time-based compliance framework, but it does not assess actual variances in grease accumulation from cooking type and/or cooking intensity. It confirms that maintenance occurred on schedule, not that the risk was effectively controlled.
Insurers increasingly focus on outcomes rather than schedules. This is why risk-based frameworks, such as the AIRAH Best Practice Guide (BPG), are gaining importance. Measuring grease accumulation and adjusting cleaning frequency demonstrates active risk management, not just procedural compliance.
Where AS 1851 applies, combining it with a risk-based approach strengthens defensibility. Where it does not apply, a structured best-practice regime may be the only credible evidence that reasonable precautions were taken.
Removing Ambiguity Before It’s Too Late
The most effective way to reduce insurance risk is to remove ambiguity before a fire occurs. This means:
- Confirming whether the exhaust is a prescribed installation
- Clearly documenting who is responsible for maintenance
- Aligning cleaning practices with recognised standards
- Keeping centralised, accessible records
- Informing insurers how the risk is being managed
When a fire occurs, insurers will form a view quickly. Clear documentation and established practices make it far easier to rebut the assumption that the risk was unmanaged.
The Real Cost of Ambiguity
The cost of ambiguity is rarely limited to property damage. It often includes:
- Delayed claim settlements
- Reduced payouts
- Uninsured business interruption
- Legal disputes between landlords and tenants
- Reputational damage and lost operating time
Most of these outcomes are avoidable. They stem not from the fire itself, but from uncertainty about how the risk was managed.
Final Thought
Kitchen exhaust fires are foreseeable. Insurers know this. When one occurs, the default question is not “What happened?” it is “Why wasn’t this prevented?”
Remove ambiguity before insurers do it for you, after a fire.