Modified bitumen roofing systems were first developed in Europe in the 1970s as an alternative to low performance asphalt systems. These are usually single-ply rolled roofing systems that are similar to ice-and-water shields, but they feature a mineral-based wear surface. There are two subtypes of modified bitumen roof: torch-down systems and peel-and-stick systems. Torch-down systems must be heated in order to activate the adhesive whereas peel-and-stick systems do not need to be heated making them safe and easy to install. Peel-and-stick roofs should always be installed by a professional roofer, but they are easier to manager for a DIY homeowner. However, torch-down application is much more challenging and poses a significant fire risk so should only be applied by professionals. Moreover, torch-down systems should not be installed on occupied buildings. Another benefit of these roofs is that their light-coloured surface helps to reflect heat and reduce energy bills. These types of roof systems are moderately priced.