Myth 1: Strictly classify and standardize according to European and American standards

It is understood that at present, the idea of ​​relevant standards in European and American countries is to classify the flammability of insulation materials and systems, and different systems are correspondingly applied to buildings with different fire protection levels. Strictly and clearly stipulate the application height of the combustible material insulation system. Basically, only the non-combustible material external insulation system is allowed above 22 meters, and the combustible material external insulation system can be used below 22 meters, even if it is used below 22 meters. When the thickness of the polystyrene board is thick (such as more than 100 mm in Germany), or when higher requirements are placed on fire prevention, certain structural fire prevention measures should be taken, such as using non-combustible materials to make fire prevention structures at the openings of doors and windows, and setting fire isolation Belt etc.

Relevant experts believe that it is ideal to strictly adopt the European and American grading standards and related regulations, but the actual situation in China is not allowed. Experts pointed out that the research on external wall insulation in developed countries such as Europe and the United States has been for nearly half a century, and has done a lot of work in basic theory, experimental research, laboratory test indicators and actual engineering application comparison, etc., and laid a good foundation, and from From their starting point, they emphasized the guiding ideology of putting people first and safety first, which we should study and learn from. Therefore, if it can be adopted directly, it is also ideal, but China's current situation must also be considered. China currently uses a large number of organic combustible insulation materials (EPS, XPS, PU, ​​etc.) for wall insulation. There is a great lack of non-combustible insulation materials such as mineral (rock) cotton board, and most of China's buildings are medium and high-level. The implementation of national standards and regulations limits organic insulation materials to less than 22 meters. Organic insulation materials will be seriously surplus without burning materials and insufficient supply, which will seriously affect the development of China's building energy conservation work.

Misunderstanding 2: Resolving the fire hazard in the construction stage can solve the problem of external insulation and fire prevention

At present, there is a view that most of the fires in existing external insulation construction projects are caused by construction site fires, and there are few cases of external insulation construction engineering fires in use. Resolving the fire hazards during the construction stage can ensure the fire safety of external insulation Sex.

In terms of importance and long-term, solving the fire hazards in the use of buildings is the core of fire safety. In the fires of the existing external insulation projects in China, most of them occurred during the construction process, and there were relatively few fire cases during the use of external insulation buildings. The reason is that during the construction process, the organic thermal insulation board is exposed without any protective layer, and the construction process often encounters crossfire operations, which is prone to fire. However, few people realize that when a fire occurs in a building in use, an external insulation system with poor fire resistance can promote the fire.

The construction site fire must be paid more attention to and resolved, but solving the fire hazards in the use of buildings is the core of fire safety. This is mainly based on the following two factors: First, there are fewer people involved in the fire during the construction process, less flammable and explosive materials in the building, more escape channels, and less difficulty in rescue. The fire occurred during the use of the building is just the opposite. Once a fire occurs, the safety of personnel and property and the rescue ability of fire fighting will face a major test. Second, the construction period of external insulation is short, generally not more than 3 months, and the service life of buildings is usually more than 50 years. Therefore, in terms of the importance of personnel and property safety and the long-term use of buildings, reduce buildings Fire damage during use is particularly important.

Misunderstanding 3: only specify simple fire protection structure, no fire classification

There is a view that when the organic insulation material system is used above 24 meters, a fire isolation zone is added to each layer or two layers, and the fire protection classification of the external insulation system is not carried out.

Relevant experts believe that this view is not enough systematic science. First of all, if it is only for the thin plastering system of polystyrene board, although it is greatly relaxed than the requirements of European and American national standards, at least it is "more powerful than no", and it can also be implemented in operation. But if it is written in an authoritative standard, such an approach is too unsystematic and unscientific. Because, without grading standards, experimental methods, and judgment indicators, it is impossible to systematically evaluate the fire protection performance of various insulation systems, so that not only can the fire protection performance of various external insulation systems already included in the regulations be effectively and systematically Evaluation can not provide research direction and conduct reasonable, effective and systematic evaluation of the newly developed external insulation system in the future.

At the same time, only the fire insulation can not solve all the problems of external insulation and fire protection. First of all, the three most frequent periods of fire occurred during the construction phase. When a fire occurs at this stage, it is usually before the construction of the surface layer. Therefore, the flame may directly hit the surface of the organic thermal insulation material through the fire barrier, which can also cause the fire to spread. Secondly, the material difference between the fire insulation tape and the organic insulation material leads to an increased chance of surface cracks, which brings new hidden dangers. The fully mature fire insulation tape technology needs to be confirmed through a large number of experimental studies.