The lifecycle of a shingle roof

A roof replacement is a major investment – one that most homeowners go through at least once. So, it’s natural to wonder how long you can expect your shingle roof to last.

A roof is exposed to tremendous temperatures from the immense heat of the sun. The intensity of the heat is strongest during the afternoon hours. The sun also emits ultraviolet rays that can break down the materials and age an asphalt roof faster. The surface of an asphalt shingle is covered with granules that help protect it from the elements; otherwise, it would degrade very rapidly. In addition, your roof is exposed to moisture, pollution and other physical stress, such as hail, ice, snow and fallen tree limbs, which can further deteriorate and age the roof.

One of the main constituents of Winnipeg roofing shingles is asphalt. Its waterproofing characteristics help maintain the integrity of the roof. The asphalt also secures the granules to the surface of the shingle and adds to its overall strength. Asphalt is a petroleum derivative consisting of oils that contribute to the elasticity and pliancy of shingles. Over time, the oils migrate to the surface of the shingle and are eroded by rain, snow, and ice. New oils will then rise to the surface to replace those that were displaced. As this process continues and materials are oxidized from the heat of the sun, the shingles become hardened and brittle.

Similar to the way the human body undergoes changes during the aging process, your asphalt roof will go through changes, as well. As a result of the harsh environment that your roof is subjected to, it may exhibit changes in appearance even one year after installation. It is not uncommon to see cracks and blisters while on a ladder during gutter maintenance. Keep in mind that this is an ordinary consequence of weathering that is usually not noticeable when observing the roof from your yard. As long as the roof maintains its integrity and does not leak, there is no cause for concern.

Another cause of aging for an asphalt roof is seasonal changes in the weather. For instance, during the summer months, the roof of your home is subjected to intense heat from the sun, with temperatures reaching 160 degrees Fahrenheit or greater. When a cold front enters the area, it is often accompanied by thunderstorms. The drop in air temperature in combination with the evaporation of rain from the roof can result in a sudden drop in temperature of between 50 and 100 degrees Fahrenheit. This difference in temperature causes the expansion and contraction of the supporting structure beneath the roof and places a strain on the shingles. Over time, as this process recurs, the shingles become fatigued.

In addition to exposure to the elements and other external stresses that may shorten the life of your roof, there are internal dynamics that can negatively affect the durability of your roof. Studies have shown that air space with improper ventilation prevents the air from circulating and, as a result, has higher moisture content than in attics with sufficient ventilation. Heat can cause degradation of the shingles while high levels of moisture can result in deck movement and deterioration, which in due course reduce the life of your roof.

There are numerous mechanisms that contribute to the accelerated aging in the life-cycle of asphalt roofs. From the moment the shingles are mounted, the materials of your roof begin the decomposition process. Each day, they are subjected to pounding rain, radiation and widely fluctuating temperatures. The fact is, from the moment a new roof is completed, it begins to age. A home’s roof is exposed to harsh environmental conditions and constant weather woes. Sunlight, wind, moisture from rain, hail, snow, and physical threats such as falling tree limbs, stray soccer balls, and even wildlife like squirrels and birds can all cause premature aging of a roof system.

So, how long does a shingle roof last? To get the most out of your investment, it helps to understand the three main stages in the lifecycle of a shingle roof.

The lifecycle of a shingle roof

Stage one: New roof

The new roof phase generally lasts for about two years and begins as soon as the last shingle is nailed in place. This stage in a roof’s lifecycle is a period of rapid aging, at least initially. This period is also known as the curing phase.

For up to a year or so after installation, homeowners might notice some significant granule loss, curling along the edges of some shingles (particularly during a cold weather spell), and even minor blistering. Don’t worry: this is perfectly normal and temporary as the new roof adjusts to the harsh environment and weather conditions it is constantly subjected to. As long as the roof’s integrity is sound and there are no leaks, there’s no real cause for concern.

Stage two: Mid-life roof

After the initial curing phase, a shingle roof enters an extended period of aging slowly, which lasts for the major portion of the shingles’ natural life, typically between 12 and 15 years. Signs of normal aging include: minor granule loss, cracking, and other signs of weathering, but not in any significant amount that would be cause for concern.

What is important for homeowners to remember during this relatively quiet stage of a roof’s life cycle is to keep up with roof maintenance. Regular inspections, either annually or biannually, and maintenance is critical to ensuring that all the various roofing system components are performing optimally and guarantee your roofing investment lasts a long time.

Remember, small defects can lead to major repairs that can compromise the entire roofing system and make a major dent in your wallet. Even a warranty can’t protect a homeowner from shouldering the responsibility of an ill-maintained roofing system. A warranty can be voided if there’s been extended neglect.

Stage three: old roof

After 12 to 15 years, a home’s roof is entering its declining years and the aging process generally accelerates pretty rapidly. It’s during this stage in a roof’s lifecycle that homeowners should start considering a replacement. “Sooner or later, every roof needs to be replaced, usually due to the long-term effects of weathering. If a residential roof is more than 20 years old, it is a prime candidate for reroofing.

In general, a home’s roof system is a long-lasting investment that will add beauty and security to your home for years to come. However, the actual lifespan of a shingle roof depends on proper installation and maintenance, as well as the use of quality materials.  If a roof develops leaks, it can result in more costly structural damage. Excess moisture can cause deterioration of the rafters and foundation. When you need a new roof, contact All Weather Exteriors at (204) 510-2959 or visit us online to get a free estimate or find answers to any home roofing questions.