Natural linseed oil paint for mineral surfaces
Introduction
Linseed oil paint is primarily used for painting wood surfaces, but it can also be used on mineral surfaces such as lime or cement plaster, stone, brick, or concrete for both interior and exterior applications. To do this, a linseed oil emulsion is prepared by mixing linseed oil paint with water. This emulsion provides long-lasting surface protection and is easy to maintain—surfaces painted with linseed oil emulsion are easy to clean, repel water, and are thus well-suited for kitchens, bathrooms, entryways, and other high-traffic areas. Additionally, it is moisture-permeable, creating a flexible coating that won’t peel or crack. In this article, we will explore how to properly prepare a surface for painting and create a linseed oil paint emulsion.
Surface Preparation
Before painting, ensure that the surface is clean and dry. If the surface was previously painted with lime or silicate paint, removing the old paint is not necessary. Remove any dust, dirt, or particles that could interfere with the paint’s adhesion. If necessary, wash the surface with warm water and linseed oil soap or mild household soap. Avoid using high pH cleaners. Ensure the surface is completely dry before applying the paint.
If the surface has just been plastered, allow it to fully dry and complete the carbonation process before painting, which may take up to 30 days.
Preparing the Linseed Oil Paint Emulsion
To prepare the linseed oil paint emulsion, you’ll need a cordless or electric drill with a mixer attachment and a container with a narrow diameter.
To create the emulsion, mix linseed oil paint with approximately 30% water. For example, to 1 liter of linseed oil paint, add about 350 ml of water. Pour both ingredients into a narrow container and mix thoroughly with the mixer until a smooth, yogurt-like consistency is achieved. If the emulsion becomes too thin, add a bit more paint.
For outdoor applications, we recommend adding the natural mineral additive zinc oxide (ZnO), available in our store. ZnO should be added at around 10-20% of the paint volume (20% for lighter tones, 10% for darker tones) to provide additional UV protection.
If water droplets appear on the surface during painting, it indicates that the linseed oil emulsion is not fully mixed. In this case, add a bit more paint and continue mixing.
The linseed oil emulsion can be applied with a roller, brush, or sprayer. Apply in a single coat; if the first coat does not produce a uniform finish, apply a second coat. The drying time for the paint is typically 24 hours at +20°C. After the second coat, drying time may be longer. Before applying another coat, always ensure the paint is completely dry.
If you are unsure about material compatibility, for example, if the plaster has been previously painted with a non-mineral-based paint, apply the linseed emulsion on a small area first to test the result.
Conclusion
Linseed oil emulsion is an eco-friendly and sustainable solution made with 100% natural ingredients. It is suitable for painting both exterior surfaces (facades) and interior surfaces (walls, ceilings). Painting indoors can be done without ventilation as the paint contains no toxic or harmful compounds. It smells of linseed oil, providing a pleasant painting experience.