Avoid underinsurance | Reasons and risks - NAB

What is home underinsurance?

Underinsurance means your insurance policy does not cover the full cost to rebuild or replace your home and contents. The key measure is rebuild cost, not what your property could sell for.

For example, if it costs $600,000 to rebuild your home but you are insured for $400,000, you’ll need to fund the $200,000 shortfall yourself if a major event occurred.

Underinsurance is a common issue in Australia with estimates suggesting that over 800,000 Australian homes are uninsured or underinsured. Underinsurance can also affect partial damage. Some policies include an “average clause” or coinsurance, which can reduce payouts if your home is insured for less than its true rebuild cost. This means even smaller claims may not be paid in full.

Why underinsurance is a risk if you have a mortgage

If you have a mortgage and your home is badly damaged, underinsurance can create two problems at once.

  • First, your mortgage usually remains in place even if the home is unliveable. Repayments can still be due while you are sorting out repairs, builders and insurance claims.
  • Second, if your insurance payout is not enough to rebuild, you may need to cover the gap from savings or other funds.

This shortfall can affect the choices you can make. Some homeowners delay rebuilding because they cannot afford the extra cost straight away. Others feel forced to make cheaper building choices to finish the job. In a stressful time, that can mean living in temporary accommodation for longer or juggling more bills than expected.

Reduce the risk of underinsurance

Use a realistic rebuild estimate

Avoid guessing how much cover you need. Rebuild cost is based on construction, not property value, and it can change as building costs rise. This amount is usually shown in your policy as the ‘sum insured’, the dollar amount used to assess claims. Online rebuild calculators can help you estimate a more accurate figure using details like your home’s size, age and location. Checking how this amount is set in your policy can help you see if your policy is still realistic.

Allow for extra costs beyond rebuilding

Rebuilding often involves more than replacing walls and a roof. Demolition, debris removal, meeting new council building codes and temporary accommodation can all add to the total cost. If these expenses are not included in your policy, you may need to pay them yourself. Thinking through these costs upfront can reduce the risk of a shortfall later.

Review your cover regularly

Insurance can become outdated over time, especially after renovations or changes to building costs. Reviewing your policy each year, and after renovations, extensions or upgrades, can help keep your cover aligned with your situation. Also check you have allowed for extra items that can be easy to miss, like site clean-up and council fees.

Make sure you’re protected

If you want independent guidance, government resources can be a good place to start. You’ll learn about common insurance terms, what to check in a policy, and how to avoid mistakes that lead to underinsurance. You can also treat insurance as part of your overall money picture. Learning how your home loan, savings, and protection plans fit together can help you feel more prepared.

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Terms and Conditions

The information contained in this article is intended to be of a general nature only. It has been prepared without taking into account any person’s objectives, financial situation or needs. Before acting on this information, NAB recommends that you consider whether it is appropriate for your circumstances. NAB recommends that you seek independent legal, financial and taxation advice before acting on any information in this article.

Target Market Determinations for these products are available at nab.com.au/TMD.