Self-insulation of wall

The earliest small mud hut in northern China used the wall self-insulation system. The internal and external walls and the kang all use a building material called renai, that is, in the soil mixed with a large number of wheat bran, wheat straw and other materials made of adobe. With renai base into the inside and outside wall is not only durable, and good insulation effect, warm in winter and cool in summer. Now the external wall because to meet the requirements of building energy conservation, most need to use the external wall insulation system. The external wall insulation system also has its inherent deficiencies: first, due to the limitation of materials, the design life of the external wall insulation system is generally not more than 25 years, which is different from the life of the building. Second, the exterior wall decoration has certain limitations. Third, every 3-5 years, to carry out a maintenance, maintenance, to property management. Compared with the external wall insulation system, the wall self-insulation system has its unique advantages: low cost, low maintenance cost, external decoration can be diversified, long service life. As for whether the wall self-insulation can achieve energy saving effect of 50% or even 65% energy saving effect, we can analyze from the following aspects:

1. Thermal insulation and energy saving project is a systematic project, which should be analyzed comprehensively. Whether a building is energy-saving, how much energy-saving, is determined by a variety of factors. For example, the orientation of the building, the shape coefficient of the building, the ratio of the window and wall area, the heating form, and the heat transfer and heat consumption of the envelope structure and other elements have an extremely important impact on the energy saving index. Among them, the heat transfer of the enclosure structure is affected by the roof, exterior wall, external doors and Windows, no heating stairwell, floor and ground. In other words, the exterior wall is only a part of the envelope. In the wall self-insulation system, the wall is composed of masonry and concrete components, concrete components belong to the cold (hot) bridge in the building structure, need to do separate heat insulation treatment. In this way, the real wall self-insulation can only account for a part of the outer envelope structure. How to deal with this part does not have a great impact on the total energy saving, but it determines what kind of insulation system to use. Generally speaking, in cold areas, the use of aerated concrete external wall panels or block wall. When the thickness is 200-240mm, if the cold (hot) bridge part is properly treated, it can generally meet the design standard of saving 50% energy, and can be used as a self-insulation wall. But if you want to meet the standard of energy saving of 65%, even if the thickness of the aerated concrete wall is increased to 300mm, it can not reach the standard. This requires higher requirements for the quality of aerated concrete bricks.

2. Using dense and precise blocks or special masonry mortar with thermal insulation performance, combined with advanced heating methods, performance design, aerated concrete bricks in cold areas to meet the standard requirements of energy saving 65% of energy, completely can be used as self-insulation wall.two. In the wall self-insulation design calculation, do not ignore the greater impact on energy consumption factors. As mentioned above, the heat consumption of a building is influenced by many factors. For example, the heating method has a great impact on the building energy efficiency. Shandong Province engineering construction standard "Residential Building energy saving Design Standard" DBJ 14-037-2006 clearly put forward: advocate the use of energy saving effect of low temperature hot water floor radiation heating. Compared with convection heating, ground low temperature hot water floor radiant heating can easily save energy 5-