Several factors influence modified bitumen roofing when hot mopped in asphalt or bitumen modification systems. Key considerations include the type of modifier used (such as SBS or APP), the application temperature, and the substrate condition. Additionally, environmental factors like ambient temperature and humidity during installation can affect adhesion and curing. Proper surface preparation and the quality of the mopping asphalt are also critical for ensuring optimal performance and longevity of the roofing system.