External wall insulation technology advantages and deficiencies

External wall insulation technology advantages. External wall insulation technology advantages Compared with external insulation within the wall, exterior insulation has the following advantages.

(1) Improve the service life of the main structure and reduce long-term maintenance costs. The use of external insulation technology, because the insulation layer is placed on the outside of the building envelope structure, buffers the stress caused by structural deformation due to temperature changes, and avoids structural damage caused by rain, snow, freezing, thawing, dry and wet cycles, reducing Hazardous gases and ultraviolet rays in the air erode the enclosing structure. Therefore, as long as the wall and roof insulation materials are properly selected and the thickness is reasonable, external insulation can effectively prevent and reduce the temperature deformation of walls and roofs, effectively eliminating common oblique cracks or eight-character cracks.

(2) Reduce the construction cost and increase the area of ​​house use.

(3) Basically eliminate the influence of "thermal bridge". “Thermal bridge” refers to the main channel for heat dissipation at the junction of internal and external walls, structural columns, frame beams, and door and window holes.

(4) Improve the thermal performance of the wall. When external insulation is used, the main structural material with high vapor permeability is located inside the insulation layer. As long as the insulation material is properly selected, condensation does not occur in the interior of the wall. Therefore, it is not necessary to provide a gas barrier layer. At the same time, the outer insulation wall is due to the structural layer with larger heat storage capacity on the inner side of the wall. When the room is subject to unstable heat, the temperature of the indoor air rises or falls, and the wall structure layer can attract or release heat, which is beneficial to room temperature. keep it steady.

(5) Facilitate renovation of buildings. In the interior decoration, the inner insulation layer is easily damaged, and the outer insulation can avoid this problem.

In the energy-saving renovation of old buildings, the biggest advantage of adopting external insulation methods is that there is no need for temporary relocation, which does not substantially affect the normal life of users.

Insufficient external insulation technology;

(1) Domestic external insulation construction is more difficult than foreign ones. This is because China has a small number of people and a large population density. The residential building structure is mainly composed of multi-storey buildings and high-rise buildings. The foreign developed countries mainly focus on low-rise villas and a few multi-storey buildings. A high-rise residential building with a cast-in-place concrete shear wall structure. In this way, the target of external thermal insulation in China is much larger than the monolithic area and height of foreign building structures, and construction is more difficult.

(2) Some external insulation products do not pass the technology. When the wind blows, they often blow off the insulation layer. It is difficult to deal with cracks in the external insulation layer, hindering the promotion of external insulation technology. Therefore, it is recommended that relevant departments should refine the technology and construction standards for external insulation products, strictly examine and approve the system, and raise the threshold for entry.

The most mature exterior wall thermal insulation technologies are currently available; plug-in external thermal insulation materials include rock (mineral) cotton, glass wool board, polystyrene foam board (abbreviated as polystyrene board, EPS, XPS), ceramsite concrete Composite polystyrene decoration stone insulation board, steel wire mesh sandwich panels and so on.

The future of exterior wall thermal insulation technology will be more varied and colorful. The use of different insulation materials, different structures, and different technologies (manual, semi-industrial, industrialization) will coexist, while the Chinese economy is in a period of vigorous development. Due to the large scale of construction, the external thermal insulation market in China will become the most extensive and dynamic external insulation market in the world.