Polymer modified bitumen sheet membranes are applied in asphalt or bitumen modification processes by integrating them into the asphalt mix or as a surface layer. These membranes enhance the performance of the asphalt by improving its elasticity, durability, and resistance to temperature fluctuations. During application, the membranes are typically heated and adhered to the substrate, ensuring a strong bond. This modification process results in improved waterproofing and longevity of the asphalt surfaces, making them suitable for various environmental conditions.