Hydrophobizing is making a porous surface such as masonry, concrete or natural stone water-repellent by impregnating it with a water-repellent agent. This agent is usually based on silane or siloxane and penetrates into the pores of the material.
How it works
The agent penetrates into the pores and coats the pore walls. As a result, the material no longer absorbs water, yet remains vapour-open: it can keep “breathing”, so water vapour can escape to the outside.
- It is not a sealing layer or coating on the surface.
- The material stays vapour-open and lets water vapour pass through.
Benefits
- Less moisture absorption in the material
- Less rainwater penetration
- Less soiling and algae growth
- Less frost damage
- A dry wall insulates better
Limitations
- It does not work against rising ground moisture; injection is needed for that.
- It does not bridge cracks; repair cracks first.
- The effect is not permanent and must be reapplied after a number of years.
Application
- Masonry
- Concrete
- Natural stone
Related terms
- Impregnating
- Capillary
- Facade
- Vapour-open construction
- Frost
- Rain penetration
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