This calculator checks whether your house sum insured is enough to cover the full cost of rebuilding your home in New Zealand, and shows any underinsurance shortfall. Since the move to sum-insured house policies around 2013, the figure you nominate is the absolute most your insurer will pay if your home is destroyed, which means the risk of setting it too low sits squarely with you. Underinsurance is widespread, partly because building costs have climbed steeply in recent years and many people have not updated a figure set long ago, and partly because rebuilding to current standards, including demolition, professional fees, and the cost of working on a sloped or hard-to-access site, costs far more than people assume. You enter your current sum insured and your best estimate of the full rebuild cost, ideally from a rebuild calculator or a professional assessment, and the calculator shows whether you are adequately covered, the dollar shortfall if you are underinsured, and the share of the rebuild your cover would actually fund. If there is a gap, it is a prompt to get a proper rebuild assessment and lift your sum insured, because discovering the shortfall after a disaster is the worst possible time.
Rebuild cost should include demolition, professional fees and site factors. Get a professional rebuild assessment to be sure. Estimate only.
The calculator compares your sum insured with the rebuild cost. If the sum insured is lower, the shortfall is the difference, and the share covered is the sum insured divided by the rebuild cost. If your sum insured matches or exceeds the rebuild cost, you are adequately covered.
A 550,000 dollar sum insured against a 650,000 dollar rebuild leaves a 100,000 dollar shortfall, covering about 85 percent of the rebuild. On a total loss you would need to find that 100,000 dollars yourself.
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