What are the different layers on a roof and how do they contribute to the overall structure and function of the roof?

The different layers on a roof include the decking, underlayment, shingles or other roofing material, and flashing. These layers work together to provide protection from the elements, such as rain, snow, and wind. The decking provides a base for the roof, the underlayment acts as a barrier against moisture, the shingles or roofing material provide the outer layer of protection, and the flashing helps to prevent water from seeping into vulnerable areas. Together, these layers contribute to the overall strength and durability of the roof, ensuring its functionality and longevity.