About this research
This research brings together evidence on the factors that shape the cost and affordability of infrastructure. It highlights where there is opportunity to influence costs to help us make better choices and get more from our infrastructure investment.
The report builds on our prior research looking at how infrastructure delivery costs stack up compared to other countries and how factors like the cost of materials, cost of consenting, and productivity growth can impact New Zealand’s construction costs, and undertaken reviews of several major projects.
It points to making greater use of standardised and repeatable approaches, improving how projects are planned and sequenced, and taking a disciplined approach to scope and design to keep costs down.
Making every dollar count
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Key findings
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Three main factors shape infrastructure costs. These are construction input costs, construction productivity, and project scope and design.
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Different types of infrastructure have very different cost trends. Solar panel prices fell significantly over time, while real motorway costs per lane kilometre have more than tripled over the past two decades.
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Construction input prices are largely controlled by global and local factors. Construction material prices can move quickly and are largely a function of global prices. Labour costs tend to be closely linked to overall labour market dynamics.
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Productivity is important for prices. New Zealand’s overall construction productivity growth is middle-of-the-pack relative to other high-income countries.
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Scope and design are key near-term levers. Standardisation, better planning and sequencing, and stronger discipline around project scope can help improve affordability.
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Better project-level evidence is still needed. More research is required to understand how specific planning, design and scope decisions contribute to infrastructure costs.
Related research
This report builds on our prior research on infrastructure costs.
Published 2 September 2026