The performance of Siplast modified bitumen roofing is influenced by several key process parameters, including the type and concentration of modifiers (such as SBS or APP), the temperature during the modification process, and the mixing time. Additionally, the viscosity of the base bitumen and the cooling rate after modification play crucial roles in determining the final properties of the roofing material, such as elasticity, durability, and resistance to environmental factors. Proper control of these parameters ensures optimal performance and longevity.