Energy-saving renovation, building wear "warm coat"

Building energy-saving renovation, building put on "warm coat." Careful Urumqi citizens may find that many buildings in the capital before winter have been stepping up their coats. This coat is the installation of insulation materials for the wall, which is also an important part of the implementation of energy-saving projects in the capital. However, no one would have thought that this good thing for the benefit of the country and the people has repeatedly raised fire alarms. Su Yunhui, vice president of the Xinjiang Academy of Building Research, talked about the topic of “Fire Protection for Wall External Apparel”. What is 'body insulation material? “It is actually a kind of thermal insulation material. Insulation means that the summer prevents the outdoor heat from entering the room and prevents the indoor heat from being emitted outside in the winter.” Why do we add insulation materials such as benzene board to the building? Su Yunhui: The first one is energy saving and emission reduction.

The energy consumption of the whole society accounts for 30% of the consumption of buildings. For every ton of high-efficiency energy-saving material, it can save 3 tons of standard coal consumption. At the same time, it can also reduce one ton of carbon dioxide, dust, and dioxide* emissions. There is also the problem of comfort. Buildings that are usually energy-efficient have a room temperature that is four to five degrees cooler than a building that is not energy efficient. Building insulation is indeed a good way to save energy and environmental protection, but this insulation material has repeatedly raised the fire alarm. September 22, 2010, Changhua Road, Urumqi City, a high-rise residential building in the construction of a high-rise residential building fire on fire. In the southeastern corner of the building, the plug of the power cord of the high-altitude operation basket was damaged and ignited, igniting the extruded sheet in the basket, and then the fire spread to the entire south and the upper part of the west surface due to wind speed and wind direction. Within 10 seconds, it burns rapidly from the top floor to the bottom. From time to time there are burning insulation boards falling. After 2 hours of fighting, the fire was extinguished and the building burned over 6,000 square meters.

Deyi Qiang, deputy chief of the fire brigade of Urumqi City, said: This fire once again warns us that we must choose non-flammable materials according to the requirements of the country for insulation materials on the external walls. According to the construction progress, some simple fire water sources should also be laid in place. On the 15th of September, another large fire ignited by thermal insulation materials took place in the building of the residential building under construction on Mount Horse Road in Urumqi. Construction workers ignited the external wall insulation benzene board during the welding. The fire burned 1000 square meters of insulation material on the external walls of residential buildings under construction, causing direct property losses of more than 70,000 yuan. According to experts, in recent years, the fire of the new CCTV building in Beijing, the two major fires in the Jinan Olympic Sports Center Stadium, and the major fires in the Gemini Jingwei 360 Degree Twin Tower have been related to the selection, design, and construction of insulation materials.

We all say that water and fire are ruthless, and the damage caused to people's lives and property by fire is indeed not small. The material that was originally installed for insulation has now caught the upper body. What is going on here? Su Yunhui: The most used insulation materials in Xinjiang market are benzene board and extruded board. Both materials are lightweight and highly efficient thermal insulation materials in terms of their characteristics. At the same time, it is non-fireproof material from the aspect of fire prevention. In the construction process, the flammable part of the outer protective layer is exposed to the outside until it is not done well.

If we do not implement the construction in the construction process, or if the fire prevention emergency measures are not in place, once there is an external source of fire, or if the fire source caused by welding or other reasons during the construction process, the igniting and insulating materials are combined with strong winds, Instantly ignite the entire exterior wall insulation. Insulate the external wall insulation system. Since 2007, with the various materials of external wall insulation materials began to be widely used in public and civilian buildings, fires also go hand in hand.

According to experts' knowledge, the materials used for the external insulation of buildings in China mainly include organic materials such as polystyrene, polyurethane, and foam rubber, and rock wool, glass wool, and other inorganic materials. The organic materials in these materials are poor in heat resistance and flammable, and when they are burned, they release a lot of heat and produce a large amount of toxic fumes. This not only accelerates the spread of large fires, but also causes casualties to trapped people and rescue workers; in particular, like polystyrene foam. Extruded polystyrene foam has poor fire resistance, and it will melt and drop at 80°C. Inorganic materials have dust and fine fibers that pollute the air and breed bacteria. At present, in China, no matter whether the building structure is in the lower, middle, or even high levels, the insulation system usually uses three kinds of insulation materials. These are all organic insulation materials and are inflammable when they are not flame-retarded. Even after the flame-retardant processing, these materials can reach the "non-flammable" at most and cannot reach the "non-combustible".

The insulation boards we use now are all flammable. How can we safely construct them? Su Yunhui: After the CCTV fire last year, the "Provisional Regulations on Exterior Insulation and Decorative Fire Protection for Exterior Walls" was promulgated. It is very clear inside. Flammable insulation materials should be covered with non-combustible objects. From another process, it is said that before the construction of the insulation material, the hot work must be completed. Is there any difference in the use of insulation materials for different buildings? Su Yunhui: The material's fire rating is divided into a grade and is a non-combustible material. Then the b1 level is non-flammable, the b2 level is flammable, and the b3 level is non-flammable. Non-curtain wall residential buildings, more than 100 meters require insulation material is non-combustible, combustion performance is a class. Between 60m and 100m, b2 or above is required, and fire barriers are installed on each floor. 24m to 60m are also b2 and above, with two separate barriers. Below 24 meters, it is also b2 or above, requiring a fire barrier on the 3rd floor.

Xinjiang is particularly long in winter and it is particularly important to do warm work. After all, the pursuit of comfort, the pursuit of the house's temperature reached 18 degrees Celsius above, the current people in the choice of external wall insulation have to pay attention? Su Yunhui: It is a very rigorous procedure to determine whether the exterior wall thermal insulation materials are qualified or not qualified. It is often difficult for users to judge whether they pass the appearance. Professionals should be allowed to do professional things. Design institutes are designed in accordance with national regulations. Targeted selection of materials. A professional construction team operates according to strict construction specifications. Apart from the material itself and the fire risk during construction and installation, what should we pay attention to in daily use? Su Yunhui: The first one is to strictly control the fire source. Let the fire source have a safe distance from the building. Don't easily pierce the wall through the wire during use. If you must wear wires, you must use sleeves to prevent the construction of hidden dangers caused by hot wires. In other words, there is a layer of mortar on the outside of the insulation layer, which is decorated for protection. However, in the use, do not remove this layer and destroy it.

After being shed, once the fire source comes into contact with the insulation, it is easy to catch fire. Su Yunhui said that this is the case. In particular, attention must be paid to this point in the course of its use. There is also a situation where we all like to put ** and shells on the occasion of the Spring Festival. Do not put a safety distance in front of buildings. Once there is a broken hole in the building, just fired into the shell, it may ignite flammable foam board. It seems that this fire-fighting consciousness has always been vigilant from design and construction to use. For foreign insulation materials, what are the mature experiences abroad? Let's take a look at the video. Developed countries have strict fire protection requirements for exterior wall insulation of important buildings and high-rise buildings. The Japanese government introduced regulations to use phenolic foam with low heat-generating and low-burning smoke as a standard fire-resistant material for public buildings. Combustibility is lower than that of phenolic foam and is not allowed in public buildings.

In China, only phenolic foam is used in the construction of high-rise public buildings such as the “Water Cube” and the Beijing Subway. In China, the most used benzene board insulation materials are prohibited from use in more than 20 states; in the United Kingdom, buildings above 18m are not allowed to use; buildings above 22m in Germany are not allowed to be used. According to experts, many manufacturers in Europe no longer produce benzene sheets with poor fire resistance, and many insurance companies have banned quality insurance for buildings that are insulated with benzene plates. What do you think are the advantages of these foreign experiences? Su Yunhui: Foreign development for many years. Initially they also used flammable high-efficiency insulation materials. After decades of use, they also found weaknesses in poor insulation of high-efficiency insulation materials. Therefore, they are now also vigorously developing energy-saving materials that are both insulating and fireproof. Foreign countries have issued relevant technical standards from the government level. In this section, they mentioned a very high level of understanding. Now our country’s technology has developed efficient materials that are both insulating and fireproof. However, based on the scale of production and the maturity of the technology, the cost of this kind of insulating and fireproof high-efficiency material remains high, and its market price is several times more than that of the current general benzene board. Therefore, there is still a long way to go before large-scale promotion. If you want to achieve the goals of safety, energy saving, fire prevention and thermal insulation, what should you do next? Su Yunhui: From my personal point of view, the first point is from the policy level. First, the state must issue relevant policies and regulations, including the objective improvement of the technological system. In this process, our researchers also have a lot of work to do for us to make unremitting efforts for the next step in the development of high-efficiency insulation, energy-saving and fire-proof materials.