Insulated panel building design: common questions for NZ industrial projects

Questions and answers

Are insulated panel warehouses and cool stores legal in New Zealand?

Yes. Metal-faced insulated panel envelopes are built across NZ for warehouses, cool stores, freezers and commercial buildings. Most Kingspan and Bondor roof and wall panels used here hold a New Zealand CodeMark certificate, which a council must accept as compliance evidence when the panel is used within the certificate's scope. When a building falls outside that scope, it is consented through an Alternative Solution. Our industrial insulated panel design service specialises in getting that documentation right.

Do insulated panel warehouses and cool stores meet NZ earthquake standards?

Yes, when the building is engineered for it. Metal-faced panels are fixed to a primary structural frame, usually a steel portal frame, so the earthquake design is really about that frame and the connections that hold the panels onto it. Those connections carry the panels' face loads and cope with the building flexing in a quake, all designed for the site's seismic zone. On our projects the frame and panel fixings are specified and signed off by a CPEng structural engineer.

Why does fire compliance matter so much for insulated panel buildings?

Because PIR and EPS panel cores are combustible insulating materials under the Building Code, and fire is where these buildings have historically gone wrong. Under Acceptable Solution C/AS1 a wall or ceiling system containing foamed plastic must achieve a Material Group Number of 3 or less, and many PIR panels test to Group 1-S. A panel forming a fire separation may also need a fire resistance rating a standard certificate does not cover, and cool store insurers often want an FM Global-approved core. Choosing the right core, whether PIR, EPS, mineral wool or a fire-tested core like XFLAM, is a real design decision.

Why do Australian insulated panel designs fail consent in NZ?

Two reasons. New Zealand sits on an active plate boundary, so our earthquake loads are far higher than most Australian designs assume under AS 1170.4, which can leave the primary frame and panel fixings under-designed for an NZ site. And an Australian CodeMark or BCA approval does not carry across the Tasman: the building still needs NZ evidence and a different fire pathway. This is a regular reason projects come to our design remediation service.

Why are New Zealand's largest panel installers based in Palmerston North relevant?

Both of New Zealand's largest insulated panel installers are based in Palmerston North. Marsco works from the same city on industrial insulated panel design close to the installers who erect warehouse and cool store envelopes.

What are the pros and cons of insulated panel construction for industrial buildings in NZ?

Pros: excellent thermal performance for cool stores, fast assembly, and a tight envelope for warehouse and industrial applications. Cons: the cores are combustible, so fire compliance and core selection need real attention; connection design must be engineered for NZ seismic zones and signed off by a CPEng structural engineer; and buildings outside a panel's CodeMark scope need an Alternative Solution. Read more on our industrial insulated panel design page, or see industrial building design for the wider commercial scope.

Can you design a cool store or warehouse with insulated panels from scratch in NZ?

Yes. This is core work for us. We design warehouse and cool store panel envelopes from concept through to consent-ready drawings on our industrial insulated panel design service, coordinating with NZ panel installers and structural engineers on the CodeMark or Alternative Solution documentation. We work with both of NZ's largest insulated panel installers, both based in Palmerston North.