The roofing industry has undergone tremendous changes in the past few decades. Even those closely involved with the industry are bewildered at times by the rapid changes in materials and technology.
Change of Traditional Materials and Decline in Quality
In the past, traditional built-up materials, made up of layers of bitumen, were the primary materials available to the roofing industry. Over the past several years, two important events changed this.
During the energy catastrophe of the 70’s and recent energy concerns, materials declined in quality as petroleum-based materials used in asphalts were refined out and used in more profitable products. Felts materials also declined in quality as natural rag used for strength and flexibility were phased out and synthetic fabric and fibers introduced, lowering performance standards.
Changes in Performance Expectations
In the past, heat was allowed to flowed by conduction from the roof into the building. This could be ignored during a time of low energy costs but as energy costs increased, it became untenable. As is often true with progress, improvements in one area brings stress or weakness to another. It has become almost routine for green building designers and energy conscious owners to increase insulation thickness to reduce heat flow. Unfortunately, a substantial insulation barrier, installed below the roof membrane, increases thermal stress as heat is held in the membrane creating increased expansion and decreasing compatibility between built-up materials.
Appearance of Liquid-Applied, Single Ply Systems
With the changes in materials came performance related issues with built-up roofs. These could not be ignored as roof life shortened and maintenance costs soared. New options were demanded and new products began entering the market. The new option which has gained considerable attention is the liquid-applied system. Seamless, lightweight and highly reflective, liquid-applied membranes have scored big and are the product of choice among professionals. After years of specifying traditional built-up roof systems, architects have opened to the new systems and techniques.
Single ply membranes have become a major choice for large commercial projects because of their ease of application, durability and long life. Examples like the recent Fresno SaveMart Center are selecting the single ply system to assure maintenance free roofs. These large commercial centers can ill afford chronic roof failures. Maintenance on these mammoths mean high-lift equipment which translates into costly repairs.
Change within the roofing industry has been good for all. It has resulted in better products and a better bottom line for the building owner.