Insulated Metal Panel (IMP), PIR or Mineral Wool Core (50mm, 75mm, 100mm, 125mm, 150mm, 200mm)
Insulated Metal Panels (IMPs) are factory-engineered sandwich panels comprising two profiled steel skins β typically 0.4β0.7mm Colorbond or Zincalume steel β bonded to a continuous insulating core. Two core technologies dominate the Australian market: polyisocyanurate (PIR) foam and mineral wool (rock wool or slag wool). PIR cores deliver superior thermal performance with a declared conductivity of 0.022 W/mK, yielding total panel R-values from approximately R2.3 (50mm) to R9.1 (200mm). Mineral wool cores offer a lower thermal conductivity of 0.033 W/mK but are non-combustible (Euroclass A1, AS 1530.1 Group 1), making them the mandated choice in fire-sensitive Type A and B construction following post-Grenfell and post-Lacrosse NCC amendments. Panel widths typically span 900β1200mm with custom lengths to 14m, and they interlock via tongue-and-groove or concealed clip joints. Major Australian brands include Kingspan (QuadCore, KS1000 RW), Lysaght Bondor (MetecnoPanel, SolarSpan), and Metecno. IMPs are used predominantly for commercial and industrial wall cladding and roofing, cold-storage facilities, and increasingly for medium-density Type C residential construction where PIR cores remain permissible.
- Commercial and industrial external wall cladding
- Low-pitch industrial roofing
- Cold storage and controlled environment rooms
- Commercial office and retail facades (Type B, MW core)
- School and education buildings
- Healthcare facilities
- Data centres
- Modular and transportable buildings
- Agricultural buildings
- Residential construction (Type C, single dwellings)
The sandwich panel concept was developed in Europe in the 1950s for refrigerated transport and cold-storage buildings, where the combination of structural skin and insulation in one element offered compelling efficiency gains. Australian adoption began in the early 1970s with polyurethane (PUR) core panels for cool rooms and abattoirs. Bondor Australia (established 1970) was among the first local manufacturers, offering steel-faced foam panels from its Victorian plant. Through the 1980s, PIR progressively replaced PUR as the dominant foam core, offering improved thermal performance and better high-temperature stability. Mineral wool cores entered the commercial market in the 1990s, initially for fire-rated applications in food processing and pharmaceutical facilities. The 2000s saw major expansion into commercial office facades and retail construction as architects recognised the speed and thermal efficiency benefits. Kingspan's acquisition of Australian distributors and the establishment of local manufacturing capacity brought European product sophistication β concealed-fix profiles, factory-applied coatings, and enhanced joint systems β to the local market. The Lacrosse apartment fire in Melbourne's Docklands (November 2014) triggered the first serious regulatory scrutiny of combustible cladding in Australian construction. The subsequent Grenfell Tower disaster (June 2017) accelerated regulatory action nationally. The ABCB's 2019 NCC amendment introduced performance requirements for external walls of Type A and B buildings referencing AS 5113, effectively prohibiting non-compliant combustible cladding systems including PIR-core IMPs above prescribed heights. State governments including Victoria, New South Wales, and Queensland enacted additional rectification programs and procurement restrictions. This regulatory shift drove rapid growth in the mineral wool IMP segment from 2019 onwards, with manufacturers investing in new production lines and updated CodeMark certifications for compliant mineral wool panel systems. Current product development focuses on QuadCore and phenolic foam hybrids that aim to bridge the thermal performance gap between PIR and the non-combustibility of mineral wool.
DISCLAIMER: This specification document is generated from the CLAD Materials Atlas Database. Information is for general guidance only and does not constitute professional engineering advice. Values are typical and may vary by batch, manufacturer, and production run. Verify suitability for specific project applications independently.