An aliphatic, elastomeric, one-component polyurethane coating. When applied over one-component polyurethane-based roof waterproofing systems, it forms a protective membrane against chalking caused by solar radiation exposure. It maintains its mechanical properties in temperatures ranging from -40°C to +80°C and offers high resistance to abrasion, hydrolysis, standing water, and frost. It ensures long-term protection of the top waterproofing coat and resistance to mechanical and thermal stresses. It is also suitable for foot traffic. Ideal as a topcoat for WATERPROOF PU 700 of DUROSTICK, enhancing resistance to solar radiation while preserving and prolonging its advantages and properties over time.