The Rockwool and mineral wool are insulations acting as moisture barrier. They are water-resistant solutions, do not waterproof the facades (they are fibrous and porous materials) or prevent leaks, but they are non-hydrophilic solutions, that is, they have no affinity for water, and they are not high osmotic
Although there are filtrations or condensations that generate large amounts of water or moisture or water vapor, the mineral or rock wools will not absorb it or trap it from the environment in any case, since its classification in front of humidity is < mu1 (i.e. 1 m3 may contain less than 1 liter of water), extremely easy to evaporate or eliminate by the material quickly.
The mineral wools are products of mineral origin in whose processing minerals have been used, that is, basaltic rocks in the case of rock wool, and silica sand in the case of mineral wool glass. They are recognized internationally as acoustic insulators, for their flexible structure, and thermal, for their interlacing that keeps the air motionless, and they are also incombustible, due to their inorganic origin.
Many of the damages that occur in a building have their cause in the harmful action of humidity. When humidity is introduced into a building, it causes different problems such as: reduction of thermal protection, degradation of materials, appearance of mold and fungi, etc.
If your façade generates condensations and moisture problems, including molds, you need materials with characteristics of a good behavior against water; materials such as cellulose or wood fiber are not recommended; the only materials that guarantee the quality of the insufflated insulation Materials in these cases are rock wool and mineral wool.
The same occurs in dwellings in very humid or cold climates, with mountainous areas or with high rainfall or high humidity, such as the Pyrenees or Esaki, in which case it is also advisable to isolate the facade with mineral wool or rock wool
We should also note that in Spain many facades with an air chamber, brick type face or cement plastering, are not waterproof facades, so injecting materials with the ability to absorb moisture or similar is crazy and will cause many problems in the future. The option for them is mineral wool or rock wool (rock wool product)
Mineral wool is water-repellent and non-hydrophilic. Hydrophilic is the behavior of every molecule that has an affinity for water. In a solution or colloid, the hydrophilic particles tend to approach and maintain contact with water. Hydrophilic molecules are in turn lyophobic, that is, they have no affinity for lipids or fats and do not mix with them
Rock wool or blot
Rockwool is the insulation obtained from the spinning process by heating volcanic basaltic rocks and coke mineral, up to 1500 degrees centigrade; in the liquid state, “threads” are obtained, which, in their stretching and cooling, are intertwined obtaining raw rock wool. The eraser is the material that we use without processing and it is the only version or format for insufflation. They cannot be considered natural, nor a recyclable material, but 95% of the raw material is natural (basalt)
Mineral wool is the insulation obtained from the silica mineral; in the case of mineral wool, it is obtained by recycling glass (converted silica), heating up to 1600 degrees centigrade; in a liquid state, fiber-threads are obtained, which are entangled obtaining the mineral wool in bulk or effaces. The eraser is the material that we use without processing and it is the only version or even blown format. It cannot be considered a natural material, but it can be recycled and respectful of the environment.