The 2026 Building Amendment Bill: what's actually changing
The Building Amendment Bill currently before Parliament is the largest reform of the Building Act since the Leaky Homes era. Most homeowners don't yet know it's happening. Most builders are still wrapping their heads around it. This guide pulls together what's actually in the bill, who it affects, and what to do about it now, based on the latest available draft, with citations to the bill text and Select Committee submissions.
What the bill does at the highest level
Three big changes, plus several smaller ones. First: a mandatory 10-year structural warranty on every new residential build, regardless of which builder or guarantee scheme is used. Second: a shift from joint-and-several to proportionate liability across builders, designers, and councils, fixing what got called the 'last man standing' problem of leaky-home claims. Third: greater self-certification powers for high-trust builders, with stricter penalties for those who abuse them.
Plus tidy-up changes: clarified producer-statement framework, updated definitions of restricted building work, refreshed consent process timelines, and new powers for MBIE to discipline LBPs and Registered Master Builders.
Mandatory 10-year structural warranty
Currently the 10-year warranty is opt-in. You get it if your builder is in Master Builders or NZCB, or your contract includes Stamford or Builtin cover. If your builder isn't a member of any of these and didn't take out independent cover, you have no insurance backing.
The proposed change: all new residential builds must come with a structural warranty product approved by MBIE, with minimum cover terms set by regulation. Cover would include deposit protection, non-completion, defects (2-year window), and structural failure (10 years). The premium would be incorporated into the contract price (typically 1-2%).
Proportionate liability instead of joint-and-several
The leaky-home era exposed a structural problem in NZ construction law: when something went wrong, the council was usually the only party left standing with assets to pay. Builders went into liquidation; designers shut shop. So under joint-and-several liability, councils ended up paying out billions for problems caused by others.
The proposed change moves to proportionate liability: each defendant pays in proportion to their responsibility. A council that gets 5% of the blame pays 5% of the damages, not 100% because everyone else has disappeared.
The downside for homeowners: if the actual at-fault party (builder, designer) has gone, you can't recover their share from the deeper-pocket council. The warranty scheme above is the offsetting protection. It puts a backstop in place that doesn't depend on solvency of the builder.
Self-certification for high-trust builders
MBIE has proposed an 'authorised builder' scheme: builders with strong compliance history and additional qualification can self-certify certain types of work without council inspection at every stage. The goal: cut consent processing time on routine builds.
The trade-off: tighter penalties for any self-certifying builder who abuses the privilege. Fines up to $500,000 and immediate licence cancellation are on the table for proven breaches.
Most existing LBPs won't qualify for this. It's expected to start as a narrow scheme for builders with multi-year clean records and additional training. Worth tracking as the rollout details emerge.
Consent process tweaks
Statutory consent target tightens. Councils will be required to meet '80% of consents within 3 working days for simple cases', a much higher bar than the current 20 working days for complex consents. Simple cases include single-storey houses on flat sites with standard cladding.
Penalties for council delay are introduced: fee refunds for missed targets, escalating to compensation in some cases.
Overseas building products: a clarified pathway for accepting CodeMark-equivalent international certifications. Currently most overseas products require expensive NZ-specific certification. This is intended to bring more product choice and competition to the market.
What this means for you right now
If you're a homeowner planning a build in 2026-2027:
- Confirm the warranty position with your builder. If they're not in RMB/NZCB and not offering Stamford/Builtin cover, ask why. Even before the bill passes, having a warranty is now the norm.
- Don't bank on proportionate liability changes saving you if your builder fails. The warranty is the actual protection.
- Watch the bill's progress. Select Committee submissions closed in early 2026; report due mid-2026. If passed, most changes likely operative late 2026 or early 2027.
What's still uncertain
The detail of the warranty regulations isn't drafted yet. Deposit cover percentages, defects window definitions, and excluded events all sit in regulations rather than the Act itself.
The self-certification scheme is conceptual at this stage. The actual criteria for an 'authorised builder' classification haven't been published.
Whether the bill passes in its current form depends on the Select Committee report and final parliamentary vote. Major reforms often shift significantly through that process.
Skip the manual checks.
CheckMyBuilder pulls the checks covered in this guide into one plain report: NZBN, LBP, court records, director history and news mentions from the official NZ sources. No afternoon spent on government websites.
Frequently asked questions
- When does the Building Amendment Bill 2026 take effect?
- Bill is currently before Parliament. If passed mid-2026, most provisions likely operative late 2026 or 2027 with phased commencement.
- Will the mandatory 10-year warranty apply to renovations?
- As currently drafted, it applies to new residential builds. Major renovations over a threshold may be included; the threshold is to be set by regulation. Minor renovations are unlikely to be covered.
- What does proportionate liability mean for leaky homes?
- Existing claims aren't affected. The change is prospective. Leaky-home claims continue under the current joint-and-several regime, subject to the 10-year long-stop in section 393.
- Do I need to do anything as a homeowner before the bill passes?
- Make sure your current build has warranty cover that meets the existing schemes (Master Build, Halo, Stamford, Builtin). Don't wait for the mandatory regime. Protection that already exists is better than future protection that may not arrive in time.
Related guides
This guide is general information for NZ homeowners and is not legal or financial advice. Names of registers, associations and dispute bodies are accurate at time of publication. Always confirm critical details on the official source before acting.