Kostas & Anor v HIA Insurance Services Pty Limited t-as Home Owners Warranty & Anor

The High Court of Australia considered an appeal by the applicants, Mr Kostas and his wife, against the respondents, HIA Insurance Services Pty Limited (trading as Home Owners Warranty) and the Builders Warranty Insurance Company. The dispute concerned the interpretation of a home owner's warranty insurance policy and the extent of the insurer's liability for defects in a dwelling. The applicants sought to recover costs associated with rectifying alleged defects in their home, which they claimed were covered by the policy.

The central legal issue before the High Court was whether the policy of insurance provided cover for the rectification of defects that were not structural in nature, but which nonetheless rendered the dwelling unfit for habitation. Specifically, the Court had to determine the proper construction of the policy's wording, particularly clauses relating to "major structural defects" and the insurer's obligation to indemnify the home owner for losses arising from such defects. The Court also considered the interplay between the policy's terms and the relevant statutory provisions governing home owner's warranty insurance in New South Wales.

The High Court analysed the policy's terms and conditions, noting that the policy provided cover for "major structural defects" and also for "other defects" that rendered the dwelling "unfit for habitation". The Court concluded that the policy was intended to cover a broad range of defects, not solely those that were structural. It held that the phrase "unfit for habitation" was a key criterion for coverage, and that defects, even if not structural, could render a dwelling unfit for habitation and thus fall within the scope of the insurance. The Court emphasised that the purpose of such insurance was to protect home owners from significant losses arising from defective building work, and that a narrow interpretation of the policy would undermine this purpose.

The High Court allowed the appeal, setting aside the orders of the lower courts. The matter was remitted to the Supreme Court of New South Wales for determination of the extent of the applicants' loss and the quantum of the insurer's liability under the policy.