Proving Progressive Damage: How Technical Evidence Strengthens Complex Insurance Claims

Insurance disputes are rarely just about whether damage exists. In complex property claims, the key questions are what caused the damage, when it occurred and whether that cause is covered under the policy.

These questions become more difficult when damage develops progressively or an insured event occurs alongside wear and tear, maintenance issues, previous repairs or underlying defects.

This may leave property owners wondering: was the damage caused by the insured event, or did an excluded or pre-existing condition cause it?

Establishing the answer can require a clear timeline of the property's condition, the insured event and how the damage developed, supported by technical evidence and expert assessment.

Read on to understand how specific types of evidence can help establish causation and strengthen a complex insurance claim. 

When Damage Has More Than One Possible Cause

Insurance policies generally respond to loss caused by an insured event, but complex claims can involve multiple contributing factors.

The Australian Financial Complaints Authority (AFCA) describes proximate cause as the dominant, effective or operative cause of a loss. It does not necessarily have to be the first or last event to occur, and determining it depends on the circumstances and evidence of each claim.

This distinction becomes particularly important when an insurer argues that damage was caused by an excluded condition such as wear and tear or inadequate maintenance.

An Australian Parliamentary inquiry identified a concerning trend in claims denied under maintenance and wear-and-tear exclusions, with more than half of decisions involving these exclusions. Importantly, the inquiry also raised concerns where expert evidence did not clearly establish a link between the alleged maintenance issue and the damage. 

Identifying a defect, however, is not necessarily the same as establishing that it caused the loss. 

Consider a commercial roof that has existing deterioration but then experiences a severe storm. If sections of the roof fail during the storm, the key question is whether the storm was the operative cause of the failure or whether the deterioration would have caused the damage regardless.

Where multiple causes are present, the policy wording becomes critical. AFCA's approach recognises that different causes may need to be considered separately, particularly where they produce distinct losses. 

That means simply identifying what is damaged may not be enough. The claim needs to establish why it is damaged. 

Progressive Damage Requires a Timeline

Where damage develops over weeks or months, establishing a clear chronology can be one 

of the most valuable forms of evidence.

A technical assessment may need to consider:

• the property's condition before the event

• when the first signs of damage appeared

• the occurrence of any insured event

• how the damage changed afterwards

• previous repairs or maintenance

• the location and extent of the damage

• whether the damage is consistent with the alleged cause

  
  

For example, a water stain that gradually expands after a major storm may tell a very different story from a stain that existed for years before the event.

This is why before-and-after evidence matters.

Previous inspection reports, maintenance records, photographs, repair invoices and building records can establish a baseline against which the post-event condition can be assessed.

Without that baseline, it can be significantly harder to distinguish new damage from deterioration that existed beforehand.

Technical Evidence Can Change the Causation Question

Photographs are important, but they generally show what the damage looks like, rather than conclusively explaining why it occurred.

That is where technical evidence becomes important.

Depending on the nature of the claim, this may include:

• independent structural engineering reports

• building or roofing assessments

• moisture testing

• thermal imaging

• drainage assessments

• material or structural analysis

• weather data

• historical inspection records

  
  

For water-related claims, for example, moisture mapping or thermal imaging may identify moisture that is not visible during a standard inspection.

An engineer may then assess whether the pattern, location and extent of damage are consistent with a particular event or indicate longer-term deterioration.

The objective is not simply to produce more evidence. It is to produce evidence that answers the causation question.

When Expert Evidence Disagrees

Technical disputes often become more difficult when the insurer's loss adjuster or engineer reaches a different conclusion from an independent expert.

This does not necessarily mean one report is automatically correct.

AFCA notes that expert evidence is considered alongside the broader circumstances of a dispute and may be critically assessed where reports conflict. Factors such as the property's age, construction, previous damage, drainage, environmental conditions, the location of an event and the extent of damage can all be relevant.

The quality of the methodology therefore matters.

A useful technical report should clearly explain:

• What was observed

• What evidence was considered 

• What caused the damage 

• Why that conclusion was reached.

A conclusion without supporting reasoning is unlikely to be as persuasive as an assessment that connects physical evidence to a clear causal mechanism.

Building a Stronger Technical Record

The earlier damage is documented, the easier it can be to establish how a loss developed.

For property owners, builders and strata managers, useful records can include:

• dated photographs and videos

• maintenance and inspection records

• previous engineering or building reports

• repair invoices

• weather records

• records of when damage was first identified

• temporary repair documentation

• correspondence with insurers, contractors and loss adjusters

  
  

Photographs should show both context and detail. Wide images establish where damage is located, while close-ups demonstrate its characteristics and extent. Where appropriate, measurements can provide additional context.

Just as importantly, records should be organised chronologically.

A clear timeline can help demonstrate that damage appeared following a particular event, progressed over time, or was materially different from the property's previous condition.

The Evidence Behind the Outcome

Progressive damage claims are rarely resolved by a single photograph or report.

They are built through evidence that establishes the property's condition, documents how that condition changed and provides a technically credible explanation for why the damage occurred.

Where wear and tear, maintenance issues and insured events overlap, this evidence can become critical. Simply identifying what is damaged is not enough; the claim needs to establish what happened, what caused the damage and what the policy responds to.

At Pharos Loss Management, we help property owners, SMEs, commercial property owners, strata managers and body corporates navigate complex insurance claims and disputes. Because in a complex insurance claim, proving the damage is only part of the process. Proving what caused it can determine the outcome. 

If you're dealing with a complex property claim or an insurer dispute around causation, scope or technical evidence, contact Pharos Loss Management for a confidential discussion. 

Pharos Loss Management

+61 478 087 092

Declan@pharos.claims

www.pharos.claims