An asphalt shingle is a type of roof shingle. They are one of the most widely used roofing covers because they are relatively inexpensive and fairly simple to install.
Product Performance: Asphalt shingles do not perform as well as they once did. Many years ago when they removed the asbestos from the shingles, they discovered that they just don’t stand up to what they once did. This is one of the main reasons that they have re-designed the shingle to what is now known has a laminated shingle.
Affordability: The efficient, high-volume production and relatively low application cost of asphalt shingles provide consumers with an overall value that’s tough for other roofing materials to match.
Low Maintenance: Asphalt shingles, when properly chosen and applied, require little or no regular upkeep, and are easily repaired if damaged.
Ease of application: Asphalt shingles are considered to be the easiest of all standard roofing materials to apply. In addition, the flexibility and strength of asphalt shingles supports their application on a wide variety of roof designs.
Fire and Wind Resistance: Asphalt shingles are manufactured to resist external fire and flammability standards, and carry Class A, B or C fire ratings, with Class A providing the greatest fire resistance.These fire ratings are defined by nationally recognized standards and tested by independent testing agencies. In addition, many asphalt shingles carrying a “wind resistance” label indicate that they have been manufactured and tested to demonstrate acceptable resistance in high-wind locations.”
Fiberglass shingles have a base layer of glass fiber reinforcing mat. The mat is made from wet, random-laid fiberglass bonded with urea-formaldehyde resin. The mat is then coated with asphalt which contains mineral fillers and makes the fiberglass shingle waterproof. Fiberglass shingles typically obtain a class “A” fire rating as the fiberglass mat resists fire better than organic/paper mats. Fiberglass reinforcement was devised as the replacement for asbestos paper reinforcement of roofing shingles and typically ranges from 1.8 to 2.3 pounds/square foot.
A newer design of fiberglass asphalt shingle, called laminated or architectural, uses two distinct layers which are bonded together with asphalt sealant. Laminated shingles are heavier, more expensive, and more durable than traditional 3-tab shingle designs. Laminated shingles also give a more varied, contoured visual effect to a roof surface.
Asphalt shingles usually last longer in cooler climates than warmer ones. Thermal shock can damage shingles, when the ambient temperature changes dramatically within a very short period of time. Proper roof ventilation can extend the service life of a roof
Aging and failure of asphalt shingles:
The protective nature of asphalt shingles primarily comes from the long-chain hydrocarbons impregnating the paper. Over time in the hot sun, the hydrocarbons soften and when rain falls the hydrocarbons are gradually washed out of the shingles and down onto the ground. Along eaves and complex rooflines more water is channeled so in these areas the loss occurs more quickly. Eventually the loss of the heavy oils causes the fibers to shrink, exposing the nail heads under the shingle flaps. The shrinkage also breaks up the surface coating of sand adhered to the surface of the paper, and eventually causes the paper to begin to tear itself apart. Once the nail heads are exposed, water running down the roof can seep into the building around the nail shank, resulting in rotting of roof building materials and causing moisture damage to ceilings and paint inside.