Modified Bitumen Roofing

Among all other commonly installed roofing systems in The United States, modified bitumen roofing has certainly been deemed the most popular, and if you look closely, it isn’t hard to understand why. With its dual protective materials asphalt and rubber or plastic membranes, this unique system is designed to provide top-notch defense against weather inclemencies, prospective punctures, and other types of external damage.

Modified Bitumen: Important Details

As an entity, modified bitumen roofing systems has an asphalt base, specifically targeting both low-slope and flat roof shapes and is accented with modifiers that impart the system with either rubber or plastic-like features. Sometimes, modified bitumen roofing can be described as sort of hybrid, as it is combined often with the materials used in built-up roofing systems. Modified bitumen roof systems are made up of several layers, and they are generally installed as two-ply systems that must be cohered.

Types of Modified Bitumen Roofing Systems

Modified bitumen roofing takes the form of one of two membranes, known as APP (Atactic Polypropylene) and SBS (Styrene-Butadiene-Styrene). The first, APP, usually adds a plasticized feature to asphalt. By adding just 30% of APP modifier, manufacturers are able to extend the modified asphalt by as much as 50% of its starting length. The APP membranes are applied either through torching or heat welding, though it is recommended that you do not torch-apply these membranes to wooden decks. This membrane gives the system its ability to obtain flexibility while also maintaining superior strength.

SBS membranes are normally installed and applied either in hot masses of asphalt or in cold adhesive.  SBS membranes give asphalt a rubber-like property, as opposed to the plasticity provided by APP. Certain SBS modified membranes have an a sticky-like backing and are able to adhere on their own, though they have a base that has to be nailed down before it is lathered with the self-adhering substance. SBS also must be coated with a layer that shields it from harmful UV rays.

Understanding the Benefits and Risks

With modified bitumen roofing being the current most popular roofing system in North America, it only makes sense that it has high-performance reviews. Modified bitumen roofing isn’t just great for waterproof and withstanding harsh weather conditions; its strength also allows it to sustain several penetrations that may occur in roof areas that are exposed to potentially-threatening externalities. In the event that damage or wear-and-tear does occur, modified bitumen is normally easy to repair without the need for adhesives or solvents because it is cooperative with asphalt shingles and compounds.

Although modified bitumen roofing systems are ideal in many cases, it is important to note that they are at a higher risk for a fire than other roofing systems. Luckily, trained professionals are skilled and well-equipped to avoid such an occurrence. Still, some fires have occurred in instances in which a wooden frame was exposed to torching, while others are to blame on the invasion of sawdust in empty crevices.