Insulation materials for steel structures are classified according to their material properties and are roughly divided into organic materials, inorganic materials, and composite materials. Different insulation materials have different performances and prices. This article will summarize several types of insulation materials for the exterior wall collected by the editor. They are arranged in order according to the insulation material performance, that is, the value of thermal conductivity. And introduce the composition, effect illustration, and application value.
A vacuum insulated panel, thermal conductivity 0.008W/（mK）
Vacuum insulation board is a kind of high-efficiency insulation board made of the inorganic fiber core material and high gas barrier composite film through vacuum encapsulation technology and covered with special interface mortar.
picture1- vacuum insulated panel
Vacuum insulation panels possess the lowest thermal conductivity among existing thermal insulation materials. Its biggest advantage is that its insulation performance is better than all other insulation materials. However, the board also has fatal defects, such as the vacuum is difficult to maintain. If it breaks, the insulation performance of the board will suddenly drop. Secondly, the existing construction process leads to too many board seams and thermal bridges and causing a great risk of condensation. Furthermore, the flatness of the construction is also more difficult to control.
B aerogel, thermal conductivity 0.02W/（mK）
Aerogel materials are known as the lightest solids in the world. It is made of nano-silica aerogel as the main material and compounded by a special process. It possesses the characteristics of high-temperature resistance, low thermal conductivity, low density, high strength, green environmental protection, waterproof and non-combustible.
Aerogel is a rare material that integrates thermal insulation performance and fire protection performance. However, even in Europe, this material is not widely used in the field of construction engineering. On the one hand, the cost of this product is too expensive, on the other hand, for the main components of the external insulation system that withstands the heating and cooling cycle, the product needs to withstand more tests.
C polyurethane, thermal conductivity 0.024W/（mK）
The best performance among the single organic thermal insulation materials is polyurethane. According to the process, it is divided into on-site foaming polyurethane and factory-made rigid foam polyurethane board.
The on-site foamed polyurethane has very good integrity and waterproofness, so it is very suitable for roof insulation and waterproofing. It is applied to the insulation in the dry hanging curtain wall, and the construction operation is convenient. Rigid foam polyurethane board is a derivative product. Due to poor dimensional stability, there is not much difference in relative expansion polystyrene board.
D Graphite polystyrene board, thermal conductivity 0.033W/（mK）
Graphite polystyrene board is a kind of expanded polystyrene board. It is a classic product of chemical giant BASF. Infrared reflector is added to the raw material of polystyrene. This substance can reflect heat radiation and improve EPS thermal insulation performance by 30 %, at the same time, the fire performance is easily achieved from B2 level to B1 level.
Picture4- graphite polystyrene board
E expanded polystyrene board, thermal conductivity 0.039W/（mK）
The full name is expanded, polystyrene board. This is the most widely used thermal insulation material. Generally used in thin plastering system, integrated thermal insulation decoration system, large mold built-in system, and steel wire grid plate system. This material occupies a large proportion in both domestically and abroad thermal insulation system market.
Picture5- expanded polystyrene board
F rock wool board, thermal conductivity 0.040W/（mK）
Rock wool board refers to a kind of mineral fiber made of natural rock as the main raw material, melted under high temperature, mixed with a certain proportion of binders and additives, then pressed and cut into a hydrophobic type insulation board. Rock wool board is the second most widely used in Europe, mainly used in high-rise building parts with strict fire protection requirements.