On the external wall insulation technology and energy-saving materials

[Abstract] With the energy saving and environmental protection requirements continue to increase, building maintenance of the structure of the insulation technology is also increasing, especially in external wall insulation technology has developed rapidly, and become an important building energy conservation technology . At present, the building's exterior wall often used mainly in insulation, thermal insulation and other methods, for the development of new technologies, new energy-saving materials to enhance the development and use, so that the building energy really be implemented.

[Keywords:] exterior wall building energy saving building materials

Building energy efficiency is the implementation of national energy conservation policy, environmental protection and the main content is to implement the national economy, an important component of sustainable development. In 1995, the Ministry of Construction promulgated the <"Urban Building energy conservation Regulations>> and other documents, the << energy conservation design standard <heating residential buildings>>> JGJ26-95 as mandatory standards, while the Ministry of Construction and on October 1, 2000 issued Decree No. 76 <<energy conservation regulations>>, is not projects meet energy efficiency standards shall not be approved for construction.

In this series of energy-saving policies, regulations, standards and mandatory provisions under the guidance of China's energy-saving housing construction work continued to deepen, improve energy efficiency standards, the introduction of the development of many new energy-saving technologies and materials to promote the residential construction use. However, our current level of building energy efficiency, but also far lower than developed countries, China's building energy consumption per unit area of climate similar to the developed countries is still 3 times to 5 times. building energy-saving construction industry in China is still an important issue.

First, the external wall insulation technology
Energy-saving insulation wall construction techniques can be divided into exterior insulation and exterior insulation in two categories.

1. Inside the insulation technology and its characteristics. Wall insulation within the construction, is the increase in the exterior structure of the internal insulation layer to do. Internal thermal insulation construction fast, easy and flexible, can guarantee the construction schedule. The heat application time is longer, mature technology , construction technology and inspection standards are more comprehensive. In 2001, construction of exterior wall, about 90% of the engineering applications in thermal insulation technique. is large area of the internal thermal insulation technologies: reinforced gypsum composite polystyrene insulation board, aggregate polystyrene insulation board materials mortar, reinforced cement composite polystyrene insulation boards, polystyrene board affixed to wipe interior wall plaster and plaster particles of polystyrene insulation cracking mortar slurry pressure increases network gingham approach.

But the heat will be more use of the area occupied by "thermal bridge" problem difficult to resolve, easily lead to cracking, also affects the speed of construction, the residents of the re-decoration, hanging and fixed objects, and interior walls can easily damage the insulation. Within the insulation technical irrationality, determine its bound to be replaced by insulation.

2. Exterior insulation technology and its characteristics. External insulation is a building insulation to promote energy saving technology. Exterior insulation and the insulation than the technology is reasonable, has its obvious advantages, the use of the same size, same size and performance insulation materials, exterior insulation within the insulation effect than good. exterior insulation technology not only works for new structures, but also for transformation of old buildings for a wide range of high technology; exterior insulation outside of the main structure package, to protect the main structure, to extend the life of the building; effective in reducing the thermal bridge building structure, increase the building's available space; while eliminating condensation and improve the living comfort.

External wall insulation is currently more mature technology, have the following.

(1) plug-plug heat insulation material rock (ore) cotton, glass wool
Carpet, polystyrene foam board (polystyrene board, EPS, XPS), ceramic decorative stone-concrete composite polystyrene insulation board, steel mesh sandwich panels and so on. Which polystyrene board because of the physical properties and excellent low cost, has been in worldwide external wall insulation is widely used plug-in technology. The plug-in technology is the use of adhesive mortar or special fixings insulation materials will be posted, linked to the outer wall, and then wipe cracking mortar , pressed into the glass fiber mesh cloth to form a protective layer, and finally add surface decoration to do. This type of insulation installed plug-consuming, difficult construction and construction-led occupation period, can be subject to inspection after construction. during high-rise construction, the safety of construction workers not easy to be guaranteed. reposted elsewhere in the Research Papers Download http://www.hi138.com (2) polystyrene board and the wall forming a casting
The technology is in the concrete frame - shear wall system will be built in the architectural template of polystyrene board, the outside wall in the upcoming casting, and then pouring concrete, pouring concrete and polystyrene board for forming a composite wall. The technical solution a plug-type exterior insulation of the main problems, the advantages are obvious. As the main wall and the insulation layer of a survival, increased efficiency, shortened duration, and the safety of construction workers have been guaranteed. and in winter construction, together Benzene stiffened and the role of insulation, can reduce the external envelope insulation measures. But in pouring concrete to the attention of uniform, continuous casting, or the pressure of the concrete side of the polystyrene board in the form removal may cause deformation and wrong after the crop, affecting after the sequence construction.

Second, external thermal insulation materials
Thermal insulation materials are energy-saving materials. Insulation material is used for building envelope or thermal equipment, heat transfer resistance material or material composite, both insulation materials, including cold material. Insulation material significance, both to meet the building thermal equipment space or the thermal environment, on the other hand is to save energy. As the world of energy has become tighter, energy-saving insulation materials in the meaning more obvious. far as the general population in terms of heating, air-conditioning through the use of thermal insulation envelope material that can be the basis of the existing energy-saving 50% to 80%. According to Japan's energy practice has proved that every 1 ton of insulation material used, can save 3 tons of standard coal / year, the energy efficiency of a material 10 times the cost of production. Therefore, some countries is the second insulation material as coal, oil, natural gas, nuclear energy after the fifth-largest "energy."
1. Insulation material properties. Insulation, is to maximize the heat transfer resistance, thus requiring insulation material must have a large thermal resistance and small thermal conductivity.

The composition from the material point of view, the general thermal conductivity of organic polymers are smaller than inorganic materials; non-metallic thermal conductivity than metal materials; gaseous material is less than the thermal conductivity of liquid material, liquid material is less than solid. Therefore, when conditions permit circumstances, should make full use of organic polymer materials or amorphous inorganic material, which is beneficial for thermal insulation.

The structure from the material point of view, the apparent density decreases when the material the porosity increases, material for the large number of closed pores inside the tiny hole, the material thermal conductivity is relatively small. For foam products, to meet the thermal insulation material requirements of the apparent density of the best 16 ~ 40kg/m3.

2. Commonly used thermal insulation material. To meet the performance requirements for building energy-saving insulation materials are: polystyrene foam board (EPS and XPS), rock (ore) cotton board, glass wool felt and ultra-light The slurry particles of polystyrene insulation and so on. All of the above materials have a common characteristic is closed inside the material has a lot of holes, their apparent density are small, which is as necessary for thermal insulation materials .

Rock (ore) cotton and wool are sometimes referred to as mineral wool, they all belong to inorganic materials. Wool does not burn, lower prices, to meet the thermal insulation properties can also have some sound insulation. But rockwool the merits of very different quality, low density, good insulation properties, its tensile strength is also low, relatively poor durability.

Third, the conclusion
At present, China has developed rapidly wall insulation technology, is the focus of energy conservation. External wall insulation and energy saving technology innovation are inextricably linked materials, building energy efficiency must be the premise of the development of new energy-saving materials, must have sufficient thermal insulation materials as a foundation. the development of energy-saving materials and the exterior insulation technology has to be combined in order to truly play its role. It is because of energy-saving materials, innovation, external wall insulation technology superiority was increasingly the attention of people. Therefore, to promote foreign wall insulation technology, new energy-saving materials to enhance the development and use, so as to truly achieve building energy efficiency. Links http://www.hi138.com Research Papers Download