The water absorption of thermal insulation material is an important index, because the thermal insulation material with poor water absorption performance will greatly affect the thermal insulation effect. If the thermal insulation material is easy to absorb water, its thermal insulation performance will be greatly reduced in a humid environment for a long time.

　　Absorbent insulation materials not only can not achieve good insulation effect, but also will accelerate the aging of materials, shorten the service life. Insulation material after water absorption, its volume and mass will increase, in some extent will increase the energy consumption of the building.

　　Therefore, for different insulation materials, we need to choose materials with corresponding water absorption properties. Glass wool thermal insulation material is a kind of inorganic fiber products, because of its special physical and chemical properties, glass wool has excellent thermal insulation, sound insulation, sound absorption, fire prevention and other properties.

　　The density of glass wool insulation material is very small, so its water absorption performance is poor, will absorb water in the air, but will not absorb a lot of water. When the moisture in the air is large or the environment is humid, the glass wool insulation material may be affected to a certain extent, but its moisture resistance is better, and it is not easy to mold or rot. At the same time, in practical applications, glass wool insulation materials are usually processed, such as coating treatment, to further improve their moisture-proof and waterproof performance.

　　In short, the water absorption of glass wool insulation material is not very strong, but in a long time of wet environment, some measures still need to be taken to protect its performance. Glass wool insulation material needs to be used with waterproof layer to achieve better insulation effect.