Architects and designers are more and more creating beautiful structures that are left with the original building material like concrete, brick or stone. However, for these structures water is often a threat as it brings many deleterious elements, such as chlorides and dirt into the porous substrates.
Using a hydrophobic impregnation on these building and civil engineering structures can efficiently support the protection of the assets from water damage; even without altering the aesthetics of the original structures.
What is Hydrophobic Impregnation?
A hydrophobic impregnation is a surface applied, invisible, non-film forming protection system that can very effectively increase the durability of a concrete structure.
Due to the small size of the mono-molecular layer, there is little or no change in aesthetic appearance of the structure. Compared to film forming coating systems, the surface applied hydrophobic impregnations penetrate the surface pores and capillaries, so that they are internally lined but not filled. Hydrophobic impregnation treatment change the surface tension of mineral substrates such as concrete, render and brickwork; this produces a water-repellent surface to keep water and aggressive water soluble salts out, such as chlorides and sulphates.
Why use Hydrophobic Impregnation?
In buildings and civil engineering structures, water should generally be kept out and away to prevent deterioration and damage, with subsequent loss of value and/or function. In addition to the problems of water penetration and damp, water ingress can also bring many other deleterious soluble materials into the substrates, including salts such as chlorides and sulphates, plus other aggressive influences.
There are several different reasons for using hydrophobic impregnation:
- To prevent further damage to the substrate from freeze/thaw attack and alkali silica reaction (ASR), etc. by preventing the ingress of water.
- To prevent further damage to the steel reinforcement by limiting the substrate water content and / or other aggressive salts ingress to the structure.
- To provide increased protection as a hydrophobic primer underneath a protective coating treatment; because if there are cracks or defects in the coating due to surface defects, then the hydrophobic impregnation prevents the future penetration of water and soluble aggressive agents in the areas of the crack or defect.
- To protect the structure without changing the visual aspects (e.g. for landmarks structures).
- To reduce the extent of efflorescence or salt damage.
- To reduce the growth of micro-organisms on the surface (algae, moss, lichen etc.).
- To reduce the effects of pollution (staining, dirt pick-up, etc.).
- To improve the thermal insulation, by effectively drying out the external walls.
Specific Requirements for Different Types of Structures
Recommended Technology:
Silane based (liquid or cream)
- Deep penetration of the hydrophobic impregnation
- Reduction of water absorption
- Reduction of chloride ion diffusion
- High freeze-thaw / deicing salt resistance
- UV resistance
Recommended Technology:
Silane based (liquid or cream)
- Deep penetration of the hydrophobic impregnation
- Reduction of water absorption
- Reduction of chloride ion diffusion
- UV resistance
Recommended Technology:
Siloxane based (liquid or cream) or Siliconate (liquid type)
- Reduction of water absorption
- Reduction of efflorescence
- Reduction of dirt pick-up
- UV resistance
- Improve thermal insulation
Recommended Technology:
Silane or Siloxane based (liquid type)
- Deep penetration of the hydrophobic impregnation
- Reduction of water absorption
- High freeze-thaw resistance (when required)
- UV resistance
Product Descriptions and Typical Uses
| PRODUCT | DESCRIPTION | TYPICAL USE |
| Sikagard® -705 L |
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| Sikagard® -706 Thixo |
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| Sikagard® -703 W |
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