Modified bitumen roofing is applied through a multi-step process involving the use of polymer-modified bitumen. Initially, the base layer is installed, typically using a torch-down or self-adhering method. The modified bitumen is heated to activate its adhesive properties, ensuring a strong bond. Subsequent layers are added, often incorporating reinforcement materials for added durability. Finally, the surface is finished with granules or a reflective coating to enhance UV resistance and longevity, ensuring effective waterproofing and protection against environmental elements.