Causation: The word that sits at the centre of almost every disputed building insurance claim.
It is not a complicated word.
But once you understand what it means, and how structural engineers use it, you will understand why some insurance claims are accepted, reduced or denied.
The word is causation.
In plain English, causation is the link between the event and the damage.
Did the storm cause the damage?
Did the tree impact cause the damage?
Did the vehicle impact cause the damage?
Did the flood cause the damage?
Or was the damage already there before the event?
That is the question that often decides the outcome of a claim.
What causation actually means
When a homeowner makes an insurance claim, there is usually an event.
A storm.
A tree impact.
A vehicle impact.
A flood.
A burst pipe.
A cyclone.
An earthquake.
The event itself is only part of the story.
The insurer then needs to decide whether the damage being claimed was caused by that event, or whether it was caused by something else.
That “something else” might be gradual deterioration, wear and tear, poor maintenance, defective construction, long-term movement, corrosion, decay, previous damage, or a pre-existing defect.
This is where claims often become difficult.
A homeowner may see the damage after the storm and reasonably say, “That happened because of the storm.”
The insurer may look at the same damage and say, “No, that was already happening before the storm.”
The structural engineer’s job is to look at the physical evidence and provide an opinion on what is more likely.
Your home has a history
One thing homeowners often do not realise until they go through a claim is that their home has a history.
It has been rained on.
It has moved.
It has expanded and contracted.
It may have settled.
It may have cracked.
It may have been patched and repainted.
It may have had drainage problems.
It may have been poorly detailed or poorly built in some areas.
None of that automatically means the claim is invalid.
Older buildings can still suffer legitimate storm damage.
Buildings with defects can still be damaged by an insured event.
A pre-existing issue does not automatically explain every piece of damage observed after a storm.
But the history of the building matters because it can affect the causation opinion.
A claim is not just about whether damage exists. It is about why the damage exists.
Why causation gets disputed
Most disputed claims turn on the same basic argument.
The homeowner says:
“The damage happened because of the storm.”
The insurer says:
“The damage was pre-existing, or it was caused by gradual deterioration, defective construction or maintenance issues.”
That argument is common because insurance generally responds to events, not to the normal ageing of a building.
The hard part is working out where the line is.
Some damage is obviously new.
Some damage is obviously old.
Some damage sits in the middle.
That is where the engineer needs to inspect carefully, record the evidence and explain the reasoning.
A causation opinion should not be a guess. It should be an opinion based on the condition of the building, the damage pattern, the history provided, the photographs available, and the likely behaviour of the structure.
What happens when an engineer arrives on site
When I attend a property after an insured event, I do not usually start by staring at the crack or damaged member in isolation.
I usually start by talking to the homeowner or occupant.
I want to understand what happened, when it happened, and what changed after the event. I want to know what they saw, what they heard, what was damaged immediately, what was repaired or made safe, and what they believe was already there before the event.
That information is useful.
But it is not the whole investigation.
After being shown through the property, I like to go back through and form my own view. I take photographs. I record the damage. I look at the location, size, shape and pattern of cracking or structural distress. If cracks are relevant, I record widths where useful. If structural members are damaged, I look at how they are damaged and whether that damage makes sense in relation to the claimed event.
I also like to start wide and work inwards.
That means looking at the property from the street, around the outside, across the site, and then into the building.
What type of building is it?
How old is it?
What is it made from?
What is the roof form?
What is the wall construction?
What is the site doing?
Are there trees nearby?
Is there evidence of drainage problems?
Is there evidence of older movement or deterioration?
That context matters.
A crack in isolation tells you something.
A crack in the context of the whole building tells you more.
Connecting the damage to the event
Some causation investigations are straightforward.
If a tree has fallen through the roof, there is damage to the roof framing, ceiling framing and wall framing directly below the impact zone, and the photographs show the tree on the house, then the causal link may be obvious.
The event happened.
The damage is in the right location.
The mechanism makes sense.
The physical evidence lines up.
But storm damage is often harder.
For storm-related claims, the question is not simply whether there was a storm. The question is whether the storm is likely to have caused the damage being claimed.
Weather records can help. They may tell us what conditions were recorded near the property. But they do not usually tell us the exact wind speed at the exact house.
The wind speed at a nearby weather station is not necessarily the wind speed at the damaged building. Local terrain, shielding, surrounding buildings, trees, slope, exposure and building height can all affect the actual wind loads experienced by the structure.
So weather records are part of the picture, not the whole picture.
The engineering question is whether the damage observed is consistent with the likely effects of the event.
For example:
Is the damage in a location that makes sense for wind loading?
Is it on a part of the building that would be vulnerable?
Do the roof and wall connections explain the damage pattern?
Is there a logical load path between the event and the damage?
Is the damage fresh, or does it show signs of long-term deterioration?
Does the failure mode look sudden, or gradual?
That is the sort of reasoning that should appear in a causation report.
The pre-existing defect argument
This is where many homeowners feel blindsided.
An insurer may say that the damage was not caused by the insured event. It was already there. Or it was caused by wear and tear, defective workmanship, poor maintenance, corrosion, decay, long-term movement or some other pre-existing issue.
Sometimes that argument is right.
Sometimes it is not.
A pre-existing defect does not automatically mean the claim should fail. A building can have an existing weakness and still suffer event-related damage.
For example, an older roof may be more vulnerable than a new roof. That does not automatically mean storm damage to that roof is not storm damage.
The real question is what caused the damage being claimed.
Did the storm cause new damage?
Did the storm make existing damage worse in a meaningful way?
Was the building already so degraded that the event was not really the cause?
Was the storm simply the moment when an existing problem was noticed?
These are not always easy questions.
But they need to be answered with evidence, not assumptions.
If a report says damage is pre-existing, it should explain why. It should point to physical evidence. That might include old staining, corrosion, previous patching, dirt inside cracks, weathered fracture surfaces, long-term distortion, historic photographs, previous reports, or a damage pattern that does not line up with the claimed event.
A statement that damage is pre-existing is not enough.
The reasoning matters.
An insurance causation report is an opinion — but not a loose opinion
This is an important distinction.
A causation report is often an opinion.
It is not always a design.
It is not always a calculation package.
It is not always a certification.
It is not always a set of repair drawings.
It is not always a construction specification.
In many insurance matters, the report is an expert opinion about whether the damage observed is likely to have been caused by the insured event.
But that does not mean all opinions are equal.
An opinion can be careful, evidence-based and well reasoned.
Or it can be shallow, selective and poorly explained.
The value of the report is not just in the conclusion. The value is in the reasoning.
A useful causation report should explain:
What was inspected.
What information was provided.
What damage was observed.
What evidence was available.
What damage is likely to be related to the insured event.
What damage appears to be unrelated or pre-existing.
Why that conclusion has been reached.
What further investigation or repair is recommended, if that forms part of the scope.
The report should lead the reader through the logic.
It should not just say, “This was caused by the storm,” or “This was not caused by the storm.”
It should explain why.
What a Cornell Engineers causation report usually contains
Our reports are generally broken down into a practical structure.
What did we see?
Is it likely to have been caused by the insured event?
Why or why not?
What needs to happen next?
The report will usually include the brief, the property details, the scope of inspection, observations, photographs, discussion, conclusions and recommendations.
The scope is important.
A visual inspection is not the same as a full invasive investigation. If wall linings have not been removed, roof spaces are not accessible, or concealed structural elements cannot be seen, the report needs to say that.
Limitations are not a weakness. They are part of honest reporting.
The photographs are also important. They allow the reader to see what the engineer saw, and they help anchor the opinion to actual physical evidence.
The conclusion should then follow from the observations.
If the report jumps from photographs to conclusion without explaining the reasoning, it is weaker than it should be.
Why qualifications and local experience still matter
A report does not become correct just because an engineer signed it.
Engineers can be wrong.
RPEQs can be wrong.
Insurer-appointed engineers can be wrong.
Homeowner-appointed engineers can be wrong.
The signature is not what makes the opinion right.
The reasoning is what matters.
That said, qualifications and experience do matter.
A local structural engineer who understands how Queensland houses are built, how older houses behave, how roof and wall framing is commonly connected, how buildings deteriorate in our climate, and how local construction practice has changed over time is usually better placed to provide a useful opinion than someone who does not have that background.
That is particularly important when the report moves beyond simple observation and into structural engineering judgment, structural adequacy, load paths, repair methodology, compliance, design or certification.
There is a difference between a general opinion and professional engineering services. The distinction depends on the nature of the work being performed.
For homeowners, the practical point is this:
Do not just look for a report. Look for a sound report.
Who prepared it?
Did they inspect the property?
Do they understand the type of building?
Does the report explain the reasoning?
Does the conclusion follow from the evidence?
Red flags in causation reports
Some insurer-commissioned reports are thorough, fair and well reasoned.
Others are not.
The same can be said for reports commissioned by homeowners.
The question is not who paid for the report. The question is whether the report is sound.
Red flags include:
- A conclusion that is not supported by specific evidence.
- A report that relies heavily on general statements.
- A report that says damage is pre-existing but does not explain why.
- A report that ignores relevant photographs or history.
- A report that does not clearly identify what was inspected.
- A report that treats visible deterioration as proof that all damage is unrelated.
- A report that fails to separate old damage from new damage.
- A report that does not explain the damage mechanism.
- A report that appears to be mostly template wording.
- A report prepared without a site inspection, where a site inspection was reasonably possible and important.
Desktop reviews can have a place, especially when reviewing existing documents and photographs. But a causation opinion based only on photographs provided by others will often be weaker than one based on a physical inspection of the property.
Again, it comes back to evidence.
Assumptions are not findings.
What homeowners should do in the first 48 hours
If the structure is not safe, stay out of it.
That is the first point.
If it is safe to do so, take photographs and videos as soon as possible after the event.
- Take wide photos.
- Take close-up photos.
- Take photos from outside.
- Take photos inside.
- Take photos of every room.
- Take photos of the roof if you can do so safely from the ground or by drone.
- Take photos before make-safe works.
- Take photos after make-safe works.
The reason is simple.
The building changes quickly after an insured event.
Branches are removed. Roof sheets are lifted. Damaged materials are stripped out. Temporary supports are installed. Tarps are added. Ceilings are removed. Debris is cleaned up.
By the time an engineer attends, the building may look very different from how it looked immediately after the event.
That does not mean the claim cannot be assessed. It just means the evidence may not be as good.
Good photographs help everyone.
- They help the homeowner.
- They help the insurer.
- They help the builder.
- They help the loss adjuster.
- They help the engineer.
They may also help later if the matter ends up in an internal review, AFCA complaint, building dispute, legal process or tribunal.
Pre-event photographs are even better
The best evidence is often the evidence taken before there is a problem.
Every six months or so, take photos of your property.
Photograph the outside. Photograph the roof from the ground. Photograph retaining walls, decks, fences, ceilings, walls, wet areas and any existing cracks or movement.
You may never need those photos.
But if there is a storm, impact, flood or other insured event, they may become very useful.
- They can show what was already there.
- They can show what changed.
- They can help separate old damage from new damage.
- They can reduce argument.
- They can make the engineer’s job easier.
In insurance work, good evidence matters.
What if the insurer’s report may be right?
This is a difficult part of the process.
Sometimes the insurer’s report is broadly right.
That can be hard for a homeowner to hear, especially when they are stressed, tired, living with damage and feeling let down by the process.
But the engineering opinion still needs to be honest.
If the damage is not logically related to the insured event, or if the physical evidence suggests it was already there, the report needs to say that.
That does not mean the homeowner is being difficult.
It does not mean the building does not need repair.
It does not mean the insurer is right about everything.
It simply means that the damage may not be damage that can properly be attributed to the insured event.
That distinction matters.
What if the report does not add up?
If you receive a causation report and the conclusion does not make sense, do not focus only on the last paragraph.
Read the reasoning.
Ask:
- Does the report correctly describe the damage?
- Does it identify the claimed event?
- Does it explain the link between the event and the damage?
- Does it explain why damage is said to be pre-existing?
- Does it rely on photographs, measurements or physical evidence?
- Does it ignore relevant information?
- Does it explain the limitations of the inspection?
- Does the conclusion follow from the observations?
If the answer is no, the report may need to be challenged.
The usual starting point for an insurance claim dispute is the insurer’s internal review or complaint process. If the dispute cannot be resolved there, AFCA may be available for eligible general insurance complaints.
In Queensland, QCAT may be relevant in some related disputes, but that depends on the nature of the dispute. A dispute about an insurer’s decision, a domestic building dispute, a QBCC-related issue, a consumer/trader dispute and motor vehicle property damage are not all the same thing.
The correct pathway depends on what the dispute is actually about.
Homeowners should obtain legal advice if they are unsure which process applies.
How to challenge a denied or reduced claim
If a claim has been denied or reduced because of causation, the process usually needs to be handled calmly and in writing.
First, ask for the reports the insurer relied on.
Read them carefully. Look for the reasoning, not just the conclusion.
Second, ask the insurer for an internal review if you do not accept the decision.
Set out the reasons clearly. Do not just say you disagree. Explain what part of the report appears wrong, incomplete or unsupported.
Third, consider obtaining independent engineering advice.
If the dispute is about an engineering conclusion, it is difficult to challenge that conclusion without proper technical evidence. A homeowner’s frustration may be completely understandable, but frustration is not the same as evidence.
Fourth, use the appropriate dispute pathway.
For many general insurance complaints, AFCA is the external dispute resolution body. Other pathways may apply depending on the nature of the dispute.
The main point is to follow the process, keep records, and build the case around evidence.
What distinguishes homeowners who get better outcomes
The homeowners who do best in this process are usually not the loudest.
They are the most organised.
- They have photographs.
- They keep records.
- They communicate in writing.
- They stay calm enough to focus on the evidence.
- They ask for reports.
- They read the reports carefully.
- They obtain independent advice where it is needed.
- They follow the complaint process.
That does not guarantee success.
Sometimes the insurer is right. Sometimes the damage is pre-existing. Sometimes the engineering evidence does not support the claim.
But when the insurer’s causation opinion is weak, incomplete or wrong, a calm, evidence-based approach gives the homeowner the best chance of a fair outcome.
A note on the emotional side
A building insurance dispute is not just a technical process.
It is personal.
Your home has been damaged. You may be living with temporary repairs, water damage, structural damage, uncertainty, delays and financial pressure. You may feel like no one is listening.
That is hard.
As engineers and consultants, we need to remember that homeowners are often dealing with this process at one of the worst times in their lives.
At the same time, the process still works best when everyone stays civil and evidence-focused.
Give the engineer the information they need. Provide photographs. Provide dates. Provide previous reports if you have them. Explain what changed after the event.
But also give the process room to work.
Good evidence, properly presented, through the right channels, can make a real difference.
How Cornell Engineers can help
Cornell Engineers prepares independent structural engineering reports for homeowners, insurers, builders, loss adjusters, solicitors and dispute matters.
If your insurance claim has been disputed, reduced or denied, and the issue involves structural damage or causation, we can inspect the property and provide an independent opinion based on the visible evidence.
We can also review reports prepared by others.
Sometimes that review will support the homeowner’s concern. Sometimes it will confirm that the insurer’s report is broadly reasonable. Either way, the advice needs to be straight.
That is the role of an independent engineer.
We are not there to simply argue for whoever pays us.
We are there to inspect, record, reason and explain.
Final thought
Causation is not always simple.
Some damage is clearly caused by an insured event. Some damage is clearly pre-existing. But a lot of insurance claim work sits in the middle.
That is where evidence matters.
A good causation report should explain what was seen, what probably caused the damage, and why that conclusion makes sense.
- It should not be a guess.
- It should not be advocacy.
- It should not be a template conclusion looking for a property to attach itself to.
It should be a clear, fair and evidence-based opinion.
That is what homeowners, insurers and decision-makers should expect.