Rock wool insulation board is a kind of fluffy open fiber structure insulation material, this structure makes rock wool insulation board has good thermal insulation, fire retardant and other properties. However, this structure also makes the rock wool insulation board encounter water will undergo some changes.

Porous fiber materials have a pain point, that is, they have a certain water absorption. When the surface of the rock wool insulation board meets small water droplets, the water droplets will stay on the surface of the rock wool insulation board, because the water repellent agent is added to the rock wool insulation board during the production process. Hydrophobic agent can form a film on the surface of the material, so as to play the role of moisture-proof and waterproof. Therefore, when the surface of the rock wool insulation board meets small water droplets, there is basically no change.

When there is more and more water, the hydrophobic performance of the surface of the rock wool insulation board slowly loses the hydrophobic effect, and the rock wool insulation board will absorb water. In addition, water will also enter through the side of the rock wool insulation board, because there are countless fiber pores on the side. Water entering the insulation board will cause the quality of the rock wool insulation board to increase and volume expansion, making its originally tight structure become more loose. If soaked in water for a long time or a lot of moisture absorption, rockwool may become soft, deformed or loose, which affects its thermal insulation and mechanical strength.

Secondly, the presence of moisture will cause the insulation performance of rockwool to decline. The insulating effect of rockwool depends on its structure and the thermal conductivity of the material. When water fills the pores in rockwool, it increases heat conduction, reducing the insulation effect. This means that when rockwool is used in a humid environment, its thermal insulation performance is greatly reduced, which affects the energy efficiency and comfort of the building.

In addition, rockwool exposed to moisture for a long time can also cause mold growth and corrosion problems. Mold growth will destroy the structure and properties of rockwool, making it more easy to absorb moisture and expand; Corrosion will damage the protective layer on the rockwool surface, reducing its durability and fire resistance.

Therefore, when using rock wool, we should try to avoid its long-term contact with water or high humidity environment.

When the rock wool insulation board is invaded by water and gas, if it is not particularly serious, the rock wool insulation board can be used normally when dry. If it is particularly serious, it can not be used if it feels all softened by hand touch.