Modified roofs are becoming more and more common today. These modified roofs are an asphalt based designed for buildings that contains low slope or flat roof surfaces. This method became popular in Europe in the 1960’s and have since became popular in the US and Canada. Modified roofs have a great resistance to cold temperatures, and also high temperatures.
A few benefits of a modified roof are it has a proven track of performance, and contains a superior waterproofing characteristics. Modified Bitumen systems consist of asphalt with modifiers added to give it durability. These are either one- two- (most common), or three ply-systems. They are factory manufactured and combine the redundancy of built up roofing with the ease of application of a single-ply system.
Modified Bitumen Systems are of two kinds:
- SBS (Styrene Butadiene Styrene) systems are usually installed with hot asphalts or cold adhesives.
- APP (Atactic Polypropylene) systems in almost every case are installed using the torch method.
Both SBS and APP systems can be reinforced either with glass or with polyester. Among the advantages these systems offer:
- The rolls of these roofing materials are factory-manufactured, ensuring quality control.
- These systems are well-suited to expand or contract with the movement of the building they protect.
- The modified bitumen roof systems can be finished with a variety of surfaces that enhance their resistance.