Low-Slope Roofing Professionals
Architects, builders, contractors, roof consultants, and building owner/managers, all stand to benefit enormously from the fact that manufacturers across North America are making asphalt better and more versatile than ever before.
Thanks especially to the addition of polymers that add stretch and strength, you can now apply your roof any way you want it: hot, cold, torch or self-adhered, to meet your individual project's special needs.
Today's asphalt roofing isn't simply a better product. It's safer. Stronger. And cleaner.
Some of the most exciting advances in the low-slope asphalt roofing industry include peel-and-stick self-adhesive products, as well as new low-fuming asphalt formulations which are popular choices today, particularly when controlling asphalt fume exposure is a priority.
The beauty of cold-process adhesive application and low-fuming asphalt is that they have been used successfully on high-density, fume-sensitive occupancy type buildings such as health care facilities, schools and college campuses, food preparations centers, airports, fashion malls, fine hotels and financial/office centers, and automotive factories.
Modified bitumen sheets are composed primarily of polymer modified bitumen reinforced with one or more plies of fabric such as polyester, glass fiber or a combination of both. Assembled in factories using high quality control standards, modified bitumen sheets are made to have uniform thickness and are manufactured to have consistent physical properties throughout the
The finished roofing membrane may consist of one or more modified bitumen sheets, or may be comprised of a combination of built-up roofing (BUR) felts and one or more modified bitumen sheets. The type of substrate and the performance objectives influence the specification of the modified bitumen membrane system.
Asphalt used in manufacturing modified bitumen systems is generally modified with one of two modifiers: Atactic Polypropylene (APP) or Styrene Butadiene Styrene (SBS). These modifiers create a uniform matrix that enhances the physical properties of the asphalt.
BENEFITS OF APP MODIFIED BITUMEN
APP is a thermoplastic polymer that forms a uniform matrix within the bitumen. This matrix increases the bitumen's resistance to ultra-violet light, increases its flexibility at high and low temperatures, and increases its ability to resist water penetration.
BENEFITS OF SBS MODIFIED BITUMEN
SBS-modified bitumen membranes resist water penetration while exhibiting
superior elongation and recovery properties over a wide range of temperature extremes. This high-performance benefit makes them exceptionally durable and particularly applicable where there may be movement or deflection of the underlying deck.
SELECTING THE RIGHT SYSTEM FOR YOU.
To obtain the best roofing system possible, the designer, building owner and contractor should understand the dynamics of the roof as well as the roofing system when specifying either APP or SBS modified roofs. For more information on how to select the proper system, please contact ARMA.
Built-Up Roofing (BUR) consists of multiple layers of bitumen alternated with ply sheets (felts) applied over the roof deck, vapor retarder, and (most often) insulation.
BUR roofing systems are particularly advantageous for flat or low-sloped applications. The heart of the system is the membrane which includes the layers of bitumen, which is applied hot, and the reinforcing plies of roofing felt.
With today's technological advances in asphalt science, cold bitumen adhesives can be used in lieu of hot asphalt.
Multi-Layer Protection -- the multiple layers of bitumen and bitumen saturated "felts" make a water-resistant barrier capable of providing many years of reliable protection from the elements
Thermal Performance -- Built-up roofing systems exhibit exceptional resistance to the conduction of heat between the exterior and interior of a building, resulting in noticeable reductions in heating and cooling costs.
Fire and Uplift Resistance -- Built-up roofing systems are tested through Underwriters Laboratories and Factory Mutual Research Corporation to meet very strict fire resistance requirements and ensure adequate uplift
resistance under extreme wind conditions.
Economy -- Compared to other high performance commercial roofing systems, built-up roofing is one of the best investments on the market due to its competitive cost per year of expected service life.