This study was carried out to investigate flammability by self - extinguishing ability and flame retardancy by cone calorimeter test on foam plastic foam insulation (EPS, XPS, PUR, PF). The purpose of this study is to investigate insulation materials suitable for zero energy buildings. 1) As a result of horizontal and vertical combustion test by KS M ISO 9772 and UL 94 test method, horizontal burn ability showed low discriminative power and vertical burnability was found to be different according to the self - extinguishing and flammability characteristics of insulation. Therefore, it is considered that the test standard for the current horizontal flammability needs to be improved and improved. 2) Cone calorimeter test for EPS, XPS, PUR, PF insulation shows that the current self-extinguishing organic insulation is less than the performance of all samples tested. Even in the case of EPS core sandwich panels, the flame retardancy of the core EPS was inadequate in the entire sample. Therefore, it is very inadequate to evaluate the flame retardancy of the composite system with the total calorific value of the composite system without evaluating the flame retardancy of the core material in a large number of various composite materials and composite insulation systems, which are recently known to satisfy the semi-fire. It is very urgent to improve the systematic supplementation and management of the test report. 3) In the case of recently developed flame retardant EPS, the heat insulation performance was confirmed to be the flame retardant material or semi-fireproof material performance at the level satisfying the thermal conductivity performance of the foamed polystyrene insulation material of KS M 3808 bead method. Therefore, it can be used as an alternative technology to meet both energy performance and fire safety performance in the future zero energy architecture implementation.