Redefining Responsibility in New Zealand Building Law – a New Era for Civil Liability

Last year, the Government announced a profound structural reform to civil liability in the construction sector. The reform proposes shifting from a joint and several liability framework – under which liability is often determined by a defendant’s solvency, rather than by their actual degree of fault – to a proportional liability regime, in which liability reflects each party’s proportionate responsibility for the loss suffered.

The proposed reform has two principal components:

• Replacement of the existing joint and several liability regime with a proportional liability regime; and
• The introduction of a compulsory insurance framework, including mandatory:
  • Professional Indemnity Insurance for construction professionals; and
  • Home Warranty Insurance.

The reform is driven by the view that the current joint and several liability regime is:

• No longer fit for purpose; and
• Unfair, in that it can impose a disproportionate share of liability on solvent defendants, irrespective of the extent to which their negligence caused or contributed to loss suffered.

In practice as the law currently stands, this can result in low-fault (but solvent) parties, such as Councils, bearing a disproportionately large share of the loss, effectively subsidising high-fault (but insolvent) parties (typically builders and developers). In contrast, under a proportional liability regime, liability is confined to each defendant’s proportionate responsibility, reflecting their actual contribution to the loss.

The Government has signalled that it intends to introduce the Building Amendment Bill to Parliament later this year. Once enacted, the legislation is expected to provide for a one-year implementation period before the reforms come into force. So, the new regime is anticipated to take effect in 2027, subject to progress of the legislative process.

Overall, the shift from a joint and several liability regime to a proportional liability regime will:

• fundamentally alter litigation practice in the construction sector; and
• promote greater fairness as between defendants by aligning liability more closely with fault.

New Zealand is not starting from scratch. Australia has operated a proportional liability regime for approximately 30 years. That jurisprudence is therefore likely to provide valuable guidance on the practical operation and consequences of such a framework.

The Australian experience also demonstrates that the effectiveness of a proportional liability regime is closely linked to the availability of adequate insurance, which underpins its practical viability.

The transition to a proportional liability regime will be accompanied by consumer protection and risk-backstopping mechanisms, implemented through mandatory:

• Home Warranties; and
• Professional Indemnity Insurance.

While the proposed reform is conceptually significant, its practical operation will depend heavily on legislative detail. Critically, a number of important questions remain unresolved.

If the proportional liability regime is confined to those who perform or certify “building work” under the Building Act, there is a risk of inconsistency and unfairness as between different categories of defendants.

Parties who do not themselves perform building work – such as manufacturers and suppliers of building products – may fall outside the regime. This could create differential liability treatment within the same proceeding, undermining coherence and potentially distorting risk allocation.

The effectiveness of the proposed home warranty regime will depend heavily on its design and implementation.

Important practical considerations include:

• the cost and market availability of warranty products;
• the scope of cover provided; and
• the procedural ease with which homeowners are able to make and enforce claims under the warranty.

The currently proposed framework provides, at minimum, a one-year defects liability period and a ten-year structural warranty. However, a one-year defects period is unlikely to be sufficient in practice, particularly for non-structural defects that may not become apparent within that timeframe.

A key question will be how the home warranty regime addresses weathertightness issues, which have historically generated long-tail and high-value claims in New Zealand.

Apartment owners in buildings exceeding three storeys are not covered by the announced proposals and may therefore face recovery shortfalls.

This is a significant issue, as a substantial proportion of New Zealand’s defective building litigation concerns multi-unit residential apartment developments. The absence of warranty protection in this sector could leave a significant cohort of homeowners exposed to the “empty chair” risk inherent in proportional liability.

By drawing a clear distinction between residential and non-residential buildings, the proposed reform will likely diverge from earlier Supreme Court jurisprudence concerning the scope of duties owed in building defect claims potentially creating uncertainty.

Clear legislative drafting will be critical to address mixed-use developments (for example, buildings that are part residential and part commercial) and to clarify the allocation of liability for defects in commercial buildings. Without careful delineation, uncertainty and renewed litigation over the scope of the new regime is likely.

Ultimately, while proportional liability offers a more internally consistent model of fault-based responsibility, its effectiveness will depend on the detail of its final design, the strength of the supporting insurance framework, and its implementation. As with many structural reforms, the overarching principle may be sound but the durability and fairness of the new regime will turn on its execution.

We will continue to monitor developments closely and provide timely updates as further information becomes available.

This publication is intended as a general overview and discussion of the content dealt with. It should not be used in any specific situation, in which case you should seek specific legal advice.