Asphalt shingles usually last longer in cooler climates than warmer ones. Thermal shock is one thing that is damaging to shingles (thermal shock is what roofing materials experience when the ambient temperature changes dramatically within a very short period of time). Another factor affecting asphalt shingle roofs is attic ventilation. Proper roof ventilation has been known to extend the service life of a roof. Shingles should not be applied during cold weather. Each shingle must seal to the layer below it to form a monolithic structure. Thus, when constructing a roof, the underlying exposed asphalt must be softened by sunlight and heat.
Are generally rectangular, may have square or irregular butts, and may be divided into tabs (by slits or cut-outs) to vary their appearance. Manufacturers sometimes laminate variously shaped pieces of similar material or extra layers of granules and coating to the weathering surface to enhance the shingles’ appearance. (Refer to Laminate).
Laminate shingles (also known as architectural shingles) do not have slots and tabs but rather have an additional strip of shingle adhered (laminated) onto the base shingle and often have blended granules giving both depth and a textured appearance. They come in a variety of patterns and colours.
Are made with strips or spots of adhesive laminated to the top surface which, under certain conditions, (usually prolonged sunlight/heat); will adhere to the underside of the butts of the next overlying course. Proper adhesion will not take place if the adhesive is too cold or damp, or if it has become oxidized or covered by dust or other foreign matter. Consideration should be given at the time of application as to whether the adhesive will be effective or whether the shingle tabs should be secured by other means. CSA requires that “shingles incorporating factory-applied adhesive sealant (self-sealing shingles) shall meet the requirements of ANSI/ASTM D3161, Wind-Resistance of Asphalt Shingles”.
IKO – A Canadian Manufacturer if you want to buy Canadian.
The Malarkey brand has patented a wider nailing line for a better installation.
GAF/ELK – has developed a shingle line that has a little more granular base to give it more depth.
Certainteed has a triple laminated shingle line for a thicker appearance.