Asphalt shingles are bitumen based sheets. Bitumen is an oil-based product that is either found in deposits such as oil sands or is obtained as a by-product from the distillation of crude oil. While it is well known that petroleum products are not great for the environment and often end up in landfills; more and more recycling of bitumen is done now. What was yesterday a roofing material could be tomorrow part of a running track.
Bitumen can be installed as a roof tile or also being put on as a sheet.
The lightweight enables a smaller roof structure compared to some other roofing materials. It is also quick and easy to install; I remember during my apprenticeship putting a bitumen rolled roofing material onto a shed- considering my apprenticeship was not in a trade the fact that I was done very quickly says it all.
Advantages of asphalt/ bitumen roofing:
Lightweight and fast to install
Proven to work
Often cheaper than other roof tiles
The product can be recycled and used for roading
Disadvantages of bitumen roofing:
Not as long lasting as other options with an expected lifespan of 15 to 50 years (depending on thickness and quality)
Product is petroleum-based and while natural at present a finite resource
Asphalt/ bitumen roofing needs to be installed by an accredited installer