ASPHALT COMPOSITE SHINGLES Alan Trauger & Associates, In

Shingles have become an integral part of the overall design of virtually any residential style. Today, the roof plays a prominent role as designers introduce more complexity into sloped roof design, incorporating steeply pitched slopes and multiple intersecting rooflines for more visual roof area, on an average more than 40% of overall building exterior.

An asphalt shingle consists of base mat that is coated with asphalt to which ceramic granules are applied. Asphalt in shingles serves primarily as a waterproofing agent, holds the granules in place, and adds to the overall strength of the shingle. Fiberglass mat and organic felt are the backbone for the respective types of shingles. Fiberglass mat is produced from a uniform dispersion of very fine glass fibers and a binder that holds them together. Fiberglass mat will not absorb moisture.

Early shingles were made by saturating rag-felts with asphalt coating on each side of the saturated felt with an asphalt mineral coat, covering the top surface with mineral granules (sunlight and weather resistance) and coating the bottom with a material to prevent shingles from sticking together during storage or shipment. Beginning in the 1940’s, the felt mat was changed to zero rag content used wood fibers and cellulose (newspaper). More recently many manufacturers began producing a fiberglass mat to replace the felt. The fiberglass mat is thought to have a good tear resistance, possibly slightly better fire resistance, as well as economic advantages to the manufacturer (less asphalt used in the mat) and the roofing contractor (lighter material and easier to install.

Granules are fine-grain, opaque, crushed rocks that have been colored by a ceramic coating.

Granules serve a two fold purpose. Primarily, they block ultraviolet light from reaching the asphalt in the shingles. UV rays will prematurely age the asphalt. The second function is to color the shingles. Some shingle colors are simply a blend of three or more different colors. The color of a shingle does have an effect on the surface temperature. Darker color shingles have roof surface temperatures 40 degrees F higher than lighter colored shingles. Although studies conducted at the University of Illinois have shown that attic airspace in a properly ventilated attic under white shingles was, at most, only 4 degrees cooler than black shingles.

In certain moist areas, algae can grow on shingles. Although has no proven effect on shingle life, it can stain or discolor the shingle. This algae staining can be unattractive. The algae staining can be reduced dramatically by the use of special copper granules, that are mixed with the color granules during the manufacturing process. The effect is to produce an environmentally safe cuprous oxide wash that is dispersed by rain or other moisture. The wash inhibits growth of algae and the resulting stains. Most manufacturers warrant their shingles only against manufacturing defects.

Label the above insert – What’s growing on your roof?

SIGNS OF ASPHALT SHINGLE FAILURES & DANGERS

Common asphalt shingle failures factors include improper storage and handling of the shingles before installation, improper nailing, improper flashing, defective shingle product material leading to splitting, cracking, blistering, staining, and in some cases curling or cupping shingles. Storm damage and hail occur and need to be distinguished from defective asphalt shingle product or asphalt shingle installation errors.

Shingles have become an integral part of the overall design of virtually any residential style. Today, the roof plays a prominent role as designers introduce more complexity into sloped roof design, incorporating steeply pitched slopes and multiple intersecting rooflines for more visual roof area, on an average more than 40% of overall building exterior.

An asphalt shingle consists of base mat that is coated with asphalt to which ceramic granules are applied. Asphalt in shingles serves primarily as a waterproofing agent, holds the granules in place, and adds to the overall strength of the shingle. Fiberglass mat and organic felt are the backbone for the respective types of shingles. Fiberglass mat is produced from a uniform dispersion of very fine glass fibers and a binder that holds them together. Fiberglass mat will not absorb moisture.

Early shingles were made by saturating rag-felts with asphalt coating on each side of the saturated felt with an asphalt mineral coat, covering the top surface with mineral granules (sunlight and weather resistance) and coating the bottom with a material to prevent shingles from sticking together during storage or shipment. Beginning in the 1940’s, the felt mat was changed to zero rag content used wood fibers and cellulose (newspaper). More recently many manufacturers began producing a fiberglass mat to replace the felt. The fiberglass mat is thought to have a good tear resistance, possibly slightly better fire resistance, as well as economic advantages to the manufacturer (less asphalt used in the mat) and the roofing contractor (lighter material and easier to install.

Granules are fine-grain, opaque, crushed rocks that have been colored by a ceramic coating.

Granules serve a two fold purpose. Primarily, they block ultraviolet light from reaching the asphalt in the shingles. UV rays will prematurely age the asphalt. The second function is to color the shingles. Some shingle colors are simply a blend of three or more different colors. The color of a shingle does have an effect on the surface temperature. Darker color shingles have roof surface temperatures 40 degrees F higher than lighter colored shingles. Although studies conducted at the University of Illinois have shown that attic airspace in a properly ventilated attic under white shingles was, at most, only 4 degrees cooler than black shingles.

In certain moist areas, algae can grow on shingles. Although has no proven effect on shingle life, it can stain or discolor the shingle. This algae staining can be unattractive. The algae staining can be reduced dramatically by the use of special copper granules, that are mixed with the color granules during the manufacturing process. The effect is to produce an environmentally safe cuprous oxide wash that is dispersed by rain or other moisture. The wash inhibits growth of algae and the resulting stains. Most manufacturers warrant their shingles only against manufacturing defects.

Label the above insert – What’s growing on your roof?

SIGNS OF ASPHALT SHINGLE FAILURES & DANGERS

Common asphalt shingle failures factors include improper storage and handling of the shingles before installation, improper nailing, improper flashing, defective shingle product material leading to splitting, cracking, blistering, staining, and in some cases curling or cupping shingles. Storm damage and hail occur and need to be distinguished from defective asphalt shingle product or asphalt shingle installation errors.


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