St. Leo Bio Undercoat is the recommended preparation for all substrates with normal absorbency before application of St. Leo Bio Paint. Bio Undercoat ensures excellent adhesion and allows Bio Paint to achieve its full colour depth.

Bio Undercoat is highly breathable, plant- and mineral-based, and with no added acrylics, plastics, microplastics, plasticisers, solvents and synthetic resins.

Formulated with renewable, biodegradable ingredients that support healthy indoor air quality and significantly reduce environmental impact compared to conventional acrylic-based primers and undercoats.

Bio Undercoat is developed for easy application on most substrates with high opacity and virtually no odor during application and drying.