Concerns exist both in New Zealand and internationally about the performance in fire of insulated panel, particularly relating to the combustibility of polymer foam core materials. The focus of this paper is the most commonly used panel product in New Zealand, polystyrene insulated panel (PIP), with its core of expanded polystyrene. A series of experimental research projects were conducted to investigate the fire performance of the material. The objective of the research programme was to quantify the fire performance, using oxygen depletion calorimetry, of different construction details. In addition, laboratory experiments also investigated the influence of fire retardant treatment and the issue of fire spread in panel cavities. The major conclusion of the research was that maintaining the integrity of the metal skins of PIP had a quantifiable and significant beneficial impact on the fire performance of PIP.
