Choose the right facade system
Importance of choosing the right facade system
Choosing the right facade system is crucial for the durability and aesthetics of your home. Facade systems not only protect against environmental influences but also regulate the climate inside your home. In this article, we explore two important properties of facade paints: water permeability and breathability. We explain what these terms mean, how to measure them, and which system is best for your home, including when to choose facade painting or limewashing.
Facade preparation
Before you start painting or limewashing the facade, a thorough inspection is essential. Assess the humidity of the walls, the condition of the pointing, and whether the current paint layers or limewash are still intact. These factors strongly influence which type of paint or limewash you should choose:
- Dry and in perfect condition: Paint or limewash directly with suitable wall paint or limewash, depending on the absorption capacity of the wall.
- Not in perfect condition: Ensure thorough cleaning and repair of damage before applying the primer, paint, or limewash. Use Primer Fixation on highly absorbent surfaces to guarantee optimal adhesion.
What is a breathable facade finish?
A breathable facade finishing system allows water vapor to pass from inside to outside after the paint has dried. This process helps moisture absorbed by the substrate (such as bricks or wood) to escape, which is crucial to prevent moisture damage and mold formation. Especially exterior paints must be sufficiently breathable to allow the substrate to 'breathe'. Matte and satin-finish paints, such as Kalei Mineral, are more effective in this regard than glossy paints.
What is a water-permeable wall paint system?
Water permeability refers to how well water can flow through a material. For facades, this means how well water can penetrate through the paint to the substrate. Wall Exterior Pearl, for example, is designed to minimize water absorption, thus better protecting facades against moisture and allowing them to dry faster after a rain shower.
Which facade finish do you choose when?
| Substrate Type | Pre-treatment | Topcoat | Properties |
|---|---|---|---|
| Bricks and uninsulated plasterwork (perfectly dry) | Primer Fixation and/or Primer Wall Exterior | Wall Exterior Pearl | Average water permeability - W2 & High water vapor permeability - V1 |
| Wall Exterior | Average water permeability - W2 & Average water vapor permeability - V2 | ||
| Insulated plasterwork (perfectly dry) - Perfect substrate | No primer needed | Wall Exterior Pearl | Average water permeability - W2 & High water vapor permeability - V1 |
| Insulated plasterwork (if chalking) | Primer Fixation | Wall Exterior Pearl | Average water permeability - W2 & High water vapor permeability - V1 |
| For breathable systems | No primer needed (apply directly) | Kalei Mineral | Fully breathable system |
Painting conditions
The quality of the paintwork is determined not only by the preparation of the substrate but also by the environmental conditions during paint application:
- Temperature: Ideally between 20°C and 25°C.
- Sunlight: Avoid direct sunlight during painting or limewashing to prevent too rapid drying and unevenness.
- Relative humidity: Maximum 85%. Too high humidity can lead to poor adhesion and longer drying times.
- Wind: Avoid painting or limewashing during windy conditions to prevent dust incorporation into the paint and too rapid drying.
Conclusion
Choosing the right facade system depends on many factors, including the specific characteristics of your home and the climatic conditions in your area. We hope this guide helps you make the right choice for your home. For more advice or to purchase our products directly, visit our store or contact us.
