Insurance Gap Calculator

Construction costs have risen 38% since 2020. This tool uses ABS building cost benchmarks to estimate whether your sum insured is consistent with current rebuild costs.

ABS Building Activity 8752.0 ABS PPI Construction ICA Underinsurance Data
Homes under-insured
~80%
ICA estimate, Australian residential
Construction cost rise
+38%
Since 2020 — ABS PPI Construction
Typical gap
$150k+
On a $500k insured dwelling

Calculate Your Insurance Gap

Enter your property details to estimate whether your current sum insured covers the actual cost to rebuild. Uses ABS building cost benchmarks by state and property type.

Home Under-Insurance Estimator

Estimated rebuild cost vs your current sum insured — the gap is your uninsured exposure.

Risk Assessment
State
Property type
Floor area 180 m²
60 m²500 m²
Build quality
Current sum insured $500,000
$100k$2m
Year last reviewed
Estimated insurance gap
—
Calculating…
Coverage adequacy
Over-insured Adequate Under-insured Critical gap
Estimated rebuild cost
—
ABS cost benchmarks
Current sum insured
—
As entered above
Coverage ratio
—
Insured ÷ rebuild cost
Cost drift since review
—
Construction cost rise
Adjust inputs to see your result.

Data current to 2025-26

This calculator produces estimates based on ABS Building Activity (8752.0) average construction costs and ABS Producer Price Index data. It does not take into account your specific property, its condition, site access, local council requirements or current builder pricing. Estimates may differ significantly from actual rebuild costs. This is general statistical information only — it is not insurance advice, financial advice, or a recommendation to take any action. For an accurate sum insured assessment, obtain a valuation from a licensed quantity surveyor or speak with your insurer directly.

The under-insurance crisis

Under-insurance is one of the most consequential financial risks facing Australian homeowners, and one of the least discussed. The Insurance Council of Australia estimates that approximately 80 per cent of Australian homes are under-insured — meaning that in the event of a total loss, the sum insured would be insufficient to rebuild the property to its current standard.

The problem has worsened sharply since 2020. ABS Producer Price Index data shows construction material costs rose approximately 38 per cent between 2020 and 2025, driven by global supply chain disruptions, labour shortages in the building trades, and elevated demand during the construction boom. Many homeowners set their sum insured in 2019 or 2020 and have not reviewed it since.

The practical consequence: a home insured for $600,000 in 2020 may cost $828,000 to rebuild today at the same specification. The insurer pays only the sum insured. The homeowner carries the $228,000 shortfall — typically at the worst possible moment, immediately after a disaster.

The ICA's published guidance suggests reviewing sum insured annually and obtaining a professional assessment every three to five years. This tool uses ABS benchmark construction costs as a starting point for general awareness. It is not a substitute for professional advice and should not be relied upon to determine actual insurance needs.

Source: ICA Underinsurance Project (2022), ABS Building Activity 8752.0, ABS Producer Price Index 6427.0 (Construction materials). Not insurance advice.