Abstract: Many new roofing systems appear to have considerable advantages over conventional bituminous roofing, but most have not yet been extensively field tested. Gravel as a protective covering has been dispensed with entirely in the newer systems, so that inspection and maintenance during and after application is greatly simplified. Imperfections and damage can easily be seen and repaired. Reflective and decorative coatings are easily applied. Most systems are light in weight and have much greater elasticity than conventional systems. Promoters, however, in their enthusiasm tend to forget or ignore some of the factors that cause failure such as building movement, trapped moisture and poor workmanship. These factors still exist with the new as well as the old systems. These systems also introduce new factors such as dependence on thin layers of adhesive to provide water-tightness at narrow joints, and bridging characteristics of fluid systems over rough surfaces and joints, as well as the need to adhere strictly to recommended materials and procedures. Despite any new problems that may arise, it is certain that the percentage of roofing using these new systems will increase during the next decade.
Canadian Building Digest; no. CBD-49, ISSN:
0008-3097, Publication date:
1964-01
