When comparing a built-up roof vs. modified bitumen, it’s important to note that both are flat roof systems. Both are durable and designed to last. The main difference between them is what is used in the layers that make up the roof. A built-up roof has a base sheet, interplay sheets, and a cap sheet or other top surface layer made with a liquid coat or gravel.
A modified bitumen roof has layers made up of asphalt and plastic or rubber polymers. Modified bitumen roofs combine traditional roofing installation techniques and technology-based advantages. Both roofs are sound options for any home or business owner considering a flat roofing system.