The beginning of Asphalt Shingles:
Back in time, before we had any type of composite asphalt roofing, people used different types of materials to be protected from the elements. Some examples were mud mixed with straw, palm trees, wood, cedar shakes and in more recent times, clay tiles, concrete roofing, asbestos, slate and whatever they had in their regional surroundings at that particular time in history. In mid-19th century asphalt composite roofing was created.
In England, around 1840, C.M. Warren Company introduced the first asphalt composite roofing. It was made of woven fabric covered with a coal tar substance, and a mix of talc and powdered gravel or limestone. At first it came made in a roll but later was replaced with tile shingles, thanks to Henry M. Reynolds of Grand Rapids, Michigan. Asphalt shingles were initially 8" by 12" pieces to imitate the wood shingles. By the 1930's, after trying many different sizes, shapes and patterns, the 12" by 36" 3-Tab shingles were created. They are still in the roofing industry till this day. With time the amount of color choices started to increase at a rapid pace and decorative effects were added as well.
Felt membrane is the main ingredient in asphalt shingles. Felt membrane can be made of fiber-glass, organic fibers and even recycled paper. It is produced in a membrane roll and then saturated with asphalt (distilled crude oil). The saturated felt is passed thru a pan where the coating is applied on both sides. These coatings can be made of powdered limestone, powdered oyster shells, slate flour, etc. This helps to stabilize the mixture, make it more flexible and gives the shingle a strong barrier against the elements. Then the final step is to shower the shingle with mineral or ceramic granules of natural stones to get different colors and to reflect and protect the shingle from the ultraviolet rays from the sun. Lastly a strip of adhesive asphalt is added to each shingle. Once installed each strip will seal all the shingles to each other.
Asphalt shingles became very popular and were used to replace slate, cedar shake roofs and asbestos shingles mainly due to affordability. Asphalt shingles have dominated the residential roofing market since it's introduction. Proper installation by a professional is the main key to make this roofing system effective. The main key to properly install the shingles is to overlap them to help water move downward. Other main keys to help increase the shingles effectiveness is to install flashing around walls, dormers, skylights, chimneys, pipe boots, etc. A reliable roofing contractor should always find the best way to prevent future leaks. To maximize the life of your roof, you need proper attic ventilation and also follow the manufacturer's recommendations.
Duration and Deterioration
The durability of asphalt shingles rely heavily on the time of installation and how properly the were installed. Proper ventilation is also key to the life of the shingle. Insufficient attic ventilation causes condensation to collect under the felt. This trapped moisture causes the roof deck and shingles to deteriorate. The life of asphalt shingles is determined also on how well it's been taken care of and how well it was made. Many factors affect it's deterioration, from physical to chemical. Asphalt shingles are expected to last roughly 20 to 30 years before any serious signs of deterioration are present. Some of these signs can be warping, buckling, exposed felt membrane or fiberglass, loss of granules, cracks on the shingles and detached shingles due to loss of stickiness. Corrosive chemicals and organic growths may also affect the shingles durability. Obviously the most common sign of shingle failure is when it is no longer protecting your roof from the elements. When you start experiencing water leaks, cracked and missing shingles, when shingles are starting to show their under layers, and a very important sign of failure would be the extreme loss of granules; all which would indicate that you are definitely due for a new roof.
It is uncommon, but some people use special coatings and water repellents to help extend the life of their roof. All they are doing is covering up the problem instead of solving it. Some people even add metal zinc strips along the top ridge of the roof. It has been proven that when it rains water washes minuscule metal particles from the zinc strips and that can act as fungicide. Other techniques that help extend the life of your roof is to install a layer of reinforced underlayment along the rakes and eaves to prevent ice dams from forming where snow can collect on the roof for long periods of time. Performing regular basic maintenance to your roof like removing debris from your valleys, gutters, skylights and from around the chimney helps keep algae and mildew from accumulating. Also, trimming tree branches that are hanging over your roof helps prevent damage. Algae discoloration is the most common issue when dealing with an asphalt shingle roof. Algae discoloration can appear as dark streaks and can result in growth and byproducts of an airborne algae called gloecapsa. Power washing your roof with household chemicals or bleach might remove some of the stains but you will be reducing the life of the roof by removing the granules on the shingles and adding unnecessary chemicals to your roof.
When asphalt roofing shingles are damaged beyond repair, then it's time to call us. Many people want shingles installed on top of an existing layer, but we don't recommend this as it cuts the life of your new roof in half and you never know if you are covering rotted wood under the first layer. So we recommend that the old roof be stripped off, replace any damaged wood, replace underlayment, damaged flashing and all accessories such as pipe boots, roof vents, etc. Now most manufactures offer a wide variety of colors and shapes to choose from. If you are in the Hampton Roads area including Virginia Beach, Norfolk, Chesapeake, Portsmouth, Suffolk, Hampton, Newport News etc don't hesitate to call us. We will be glad to help you pick the roofing system that will fit your home best.
Call us for all your roofing needs (800) 757-6701.