NZS 3910 is the contract form that runs most commercial and civil construction in New Zealand. If you work in estimating, quantity surveying, or contract administration, you will deal with it. This guide covers what it is, how it works, what changed in 2023, and why it matters for anyone in commercial construction.
What Is NZS 3910?
NZS 3910 is a standard form contract published by Standards New Zealand. Its full name is NZS 3910: Conditions of Contract for Building and Civil Engineering Construction. It sets out the legal framework for how a principal (usually the client) contracts a contractor to carry out construction work.
Most NZ government and local authority projects require NZS 3910 or a derivative of it. Many private clients use it too, particularly on projects with a professional consultant team. It is the de facto standard for mid to large-scale construction in this country.
The contract operates on a principal-contractor model with an engineer (or architect) acting as the Engineer to the Contract. That engineer sits between the principal and contractor, administering the contract on behalf of the principal but with defined obligations to act fairly.
Who Uses It?
NZS 3910 applies across a wide range of projects. Government agencies, councils, NZTA, school boards, and hospital boards all use it. Most tier-one and tier-two contractors are familiar with it. On these projects, the QS or estimator needs to understand the contract before pricing, not after.
On the principal’s side, a quantity surveyor often acts as cost manager and supports the Engineer to the Contract in administering payments, variations, and claims. On the contractor’s side, the QS prices the work, manages subcontract packages, and tracks contract value through the project.
Key Provisions Every QS Needs to Know
Payment under NZS 3910 works on a progress claim and payment schedule cycle. The contractor submits a progress payment claim, and the engineer assesses it and issues a payment schedule. The principal then pays the scheduled amount. This cycle drives the entire cash flow of the project.
Variations are changes to the scope of work. The contract sets out a process for how these get instructed, valued, and agreed. A QS on either side of the contract will spend considerable time valuing variations, particularly on complex or fast-tracked projects. Getting variations right protects the contractor’s margin and the principal’s budget.
The contract includes a disputes process that starts with a notice of dissatisfaction and progresses through formal dispute resolution. Most disputes in NZ construction end up going to adjudication under the Construction Contracts Act 2002. Understanding how NZS 3910 interfaces with that Act is part of the job.
Roles under NZS 3910 matter. The Engineer to the Contract holds real power: they assess claims, issue instructions, certify payments, and grant extensions of time. When you work in post-contract administration, you are often working directly in support of, or as part of, this function.
What Changed in NZS 3910:2023?
The 2023 revision was the first major update in over a decade. Several changes reflect lessons from NZ projects and align the standard with modern practice.
The 2023 version introduces clearer language around time bars. Contractors must now give notices within defined timeframes to preserve their rights to claim. Miss the notice window and you can lose the claim. This is a risk QSs need to manage actively.
The updated standard also tightens the definition of a variation and what constitutes a legitimate instruction. Verbal instructions still happen on site, but the contract requires written confirmation. Practitioners who rely on informal arrangements expose their principals or contractors to risk.
There are also changes to how the Engineer to the Contract handles extensions of time and delay claims. The 2023 version makes the process more structured and creates clearer obligations for both parties to provide information and respond within timeframes.
If you are still working from the 2013 version, get the 2023 update. The differences are meaningful and clients and contractors are already using it on new projects.
NZS 3910 and the Construction Contracts Act
NZS 3910 does not operate in isolation. The Construction Contracts Act 2002 (CCA) sets minimum payment rights that override any contract terms. Under the CCA, contractors have a statutory right to suspend work for non-payment, and adjudication is available as a fast-track dispute resolution process.
A key point: payment claims under NZS 3910 are also payment claims under the CCA. If the principal fails to issue a payment schedule in time, the contractor can apply directly to the court for judgment. This is one reason accurate and timely payment administration matters so much.
Why This Matters for QS and Estimating Work
When you price a job under NZS 3910, the contract conditions affect your risk profile. Retention, liquidated damages, defects liability periods, and insurance requirements all affect cost. An estimator who reads the contract before pricing prices it differently from one who does not.
In post-contract work, NZS 3910 is the document you live inside. Every payment claim, every variation, every programme update is governed by it. Understanding the contract is not optional for anyone doing this work professionally.
We cover NZS 3910 in depth in our training. If you want to build a solid foundation in post-contract administration, the contract is where you start.
Learn more about our Post Contract Administration programme or enrol in the Full Estimating and Surveying Certificate to build your commercial construction skills from the ground up.
