Certificate of Acceptance: Fixing Unconsented Building Work

Sooner or later, most owners of older Auckland homes meet a piece of building work that has no paperwork. A garage conversion from the nineties. A deck a previous owner built one summer. A bathroom that appears in no consent the council holds. The question that follows is always the same: can this be made right? The honest answer is partly, sometimes, and the mechanism is called a Certificate of Acceptance. Here is what it is, what it can do, and, just as important, what it cannot.

What a Certificate of Acceptance is

A Certificate of Acceptance (CoA) is the council's formal, after-the-fact statement about completed building work, issued under sections 96 to 99 of the Building Act 2004. Where a building consent is approval before work happens and a Code Compliance Certificate is confirmation the consented work was done, a CoA is the fallback for work that went ahead outside that process: the council assesses what exists and certifies, to the extent it could reasonably ascertain, that the work complies with the Building Code.

The MBIE guidance sets out when an owner can apply. The main grounds:

• Work that needed a consent but never had one, whether done by you or a previous owner, under the current Act or the 1991 one.
• Urgent work that had to be done immediately, to protect life or property, before a consent could be obtained.
• The historical case where an old private building certifier could not or would not issue a certificate.

One hard limit sits under all of it: a CoA can only be issued for work done on or after 1 July 1992, when the Building Code came into force. Work older than that predates the Code and cannot get one, which for genuinely old alterations is usually fine, they are judged as part of a pre-Code house, not as missing paperwork.

What it certifies, and the qualifier that matters

The phrase doing the heavy lifting in a CoA is "could reasonably ascertain". The council certifies only what it could actually verify by inspecting the finished work, and it can exclude or qualify anything it could not see. Covered work is the standard example: once linings, cladding or decking are on, the framing, the fixings, the waterproofing and the flashings underneath are invisible, and the certificate will say so.

This is the structural weakness of every CoA, and it is worth sitting with. On the categories of work where compliance matters most, structure, weathertightness, anything buried in a wall, the CoA can often certify the least, because those are precisely the parts that get covered up. A consent-and-CCC process solves this by inspecting at each stage while everything is open. A CoA arrives after the fact and can only look at what is left to look at.

Three more things a CoA is not. It is not a retrospective building consent, the work's history does not change, and the property record will always show it was done outside the process. It is discretionary, the council can refuse if it is not satisfied, and can still require remediation of anything non-compliant it finds along the way. And it is not cheap: the application requires as-built plans and specifications plus evidence of compliance, and the fees include what the consent would have cost plus the council's assessment charges, payable whether or not the certificate is ultimately granted. The idea that skipping consent saves money rarely survives contact with the CoA process.

CoA versus CCC, as the market sees it

Legally, a CoA and a CCC are different instruments. Practically, buyers' lawyers, banks and insurers read them differently too, and not in the CoA's favour. A CCC says: this work was designed, approved, inspected at every stage, and signed off. A CoA says: this work happened outside the process, and the council later accepted what it could still verify. Both are far better than nothing on the record, but treating them as equivalent at sale time is a mistake, a CoA on significant work will still draw questions, and on weathertightness-relevant work, often a request for further investigation.

That is not a reason to avoid getting one. Unresolved unconsented work is worse than a CoA in every respect. It is a reason to be realistic about what the certificate buys, and to get the underlying work into genuinely sound condition rather than treating the paper as the fix.

The practical playbook for unconsented work

If you are buying: unconsented work and CoAs show up in the LIM and property file, and the cost of resolving them belongs in the price. A CoA on cladding, decks or structural changes is a prompt for a specialist look, not a reassurance to file away.

If you own it: resolving unconsented work on your own timeline is almost always cheaper and calmer than doing it under a sale deadline. The sequence is: establish what is actually there and whether it complies (which may mean opening things up), remedy what does not, then apply with proper as-built documentation.

If the work touches the building envelope: this is the case that deserves the most care. Unconsented cladding, decks, or alterations to the weathertight envelope are the highest-risk category, both for the building and for the certificate, because the critical details are hidden and the consequences of them being wrong compound quietly. Where an assessment finds the unconsented work is part of a wider weathertightness problem, the honest path is often to bring the affected envelope up to the current code properly, under a consent this time, so it finishes with a full CCC rather than a qualified acceptance. That is remediation work, and done that way, the property comes out with the stronger certificate and a solved problem instead of an accepted one.

And if you are mid-project now: never let a live job drift into CoA territory. If you discover part of your current work needed consent, stop and talk to the council before covering anything, because everything still visible is everything still certifiable.

If your Auckland home has unconsented work, or a purchase you are weighing does, and you want a straight read on what it would take to put it right properly, an on-site assessment is the place to start.