In general, external insulation surface using special polymer mortar and flexible putty, with its water problems can be resolved; but in the vapor permeability problem, academia, community controversial application, a typical argument is that, XPS board , vapor impermeable material such as polyurethane insulation board, exterior insulation is not suitable as the main material, in fact, the project has been implemented too few success stories. The so-called vapor permeability Binzhou fa?ade insulation board, actually refers to the steam from the hot side to the cold side of the diffusion migration capability. For composite building structure, with insulation layer as the dividing line, I believe that if the outer wall and the water vapor permeability of insulation resistance is greater than the sum of (and the bigger the better) wipe the surface layer and the decorative layer and, in winter , the indoor air enters through the diffusion of water wall can be smoothly exhausted to the outside, otherwise it will produce condensation in the junction of the insulation layer and wipe the surface layer, resulting in freeze-thaw damage. Therefore, the XPS panels, the insulation board in accordance with the standard provisions of Jiangsu Province, the insulation layer and the outer wall of the water vapor permeation resistance and more than wipe the surface layer and the decorative layer and, in theory, can be used in wall insulation, but it should be to strengthen its system components materials research, particularly its interface, bond research and plaster material, rather than just simply copy the EPS system constituent materials; and for material polyurethane (PU) and so it should be cautious. According to GB 97 Standard: China's current standard wall insulation will be divided into class A (non-combustible), B1 level (flame retardant), B2 level (flammable) and B3 level (flammable) 4 levels. Extrusion plate belonging organic material so only: B1 level (hard ...