Safe, sturdy and reliable are probably some of the adjectives that come to mind when you think about your ideal house. There are many factors that contribute to a house’s overall function, but the roof is one of the most important because it acts as a barrier that keeps your space safe and protected from the weather conditions outside.
While there are a variety of different roofing materials on the market, the majority of homes in North America have roofs made of asphalt roofing shingles. These roofs are complex, and it can be easy to overlook the roof when it is functioning properly. However, a thorough understanding of the materials that make up a roof, as well as common roofing terms, makes it easier to understand symptoms of roof damage and explain problems to a roofing contractor when they arise.
Anatomy of an Asphalt Shingle Roof
While the shingles are the only visible component of an installed roof, asphalt shingle roofs are made up of five different materials, each contributing to the overall function of the roof.
Roof Frame and Decking
The foundational components of your roof are the roof frame (also referred to as the roof truss), and the roof decking. The frame is the skeleton of the roof. It is usually constructed of wood, and becomes the frame that the rest of the roofing materials will sit on. The roof decking consists of thin pieces of wood usually 4’x8’, usually plywood or OSB (Oriented Strand Board), that lays over the entirety of the roof frame.
Ice and Water Shield
Ice and water shield is applied directly onto the roof decking. Like the name suggests, this material helps keep the roof safe from ice and water. It is a thin, rubberized asphalt membrane that helps protect against ice dams and wind-driven rain, both of which can drive water up between shingles. Specific regulations vary from state to state, but in all climates where snow and ice are prevalent, ice and water protectant is a necessary addition to every roofing system.
Once the ice and water protectant is in place, the roof is ready for the underlayment. Underlayment is a fabric-like barrier that is installed underneath the shingles, and protects them from any resin the roof deck may release. It can also serve as a water barrier in the event that water penetrates the shingles, and offer some measure of fire resistance.
After the underlayment is installed, the shingles can be placed. Asphalt shingles are small squares made of a fiberglass base layer, waterproof asphalt, and protective granules. The granules protect against the sun’s harmful UV rays, and the asphalt protects the roof from water intrusion.
Because of these components, shingles are able to withstand all of the weather conditions common to Virginia, including rain, snow, and sun, and are long-lasting when well maintained. Shingles developed in recent years have the ability to last up to 50 years before needing to be replaced.
Flashing is a thin sheet of metal that wraps around vertical surfaces that intersect with the plane of the roof, such as chimneys, skylights, plumbing and roofing vents, valleys, and dormers. It covers the small gaps left between the shingles and the edges of these structures, providing a watertight seal that keeps water from dribbling into your roofing system and causing damage.
Metal flashing is one of the most important components of the roof’s watertight seal, because if it fails, the gaps in the roof are exposed and become susceptible to water intrusion and damage.
Parts of a Roof Edge
All of these components lead to the roof edge. The roof edge is made up of several components that divert and direct water run-off from the roof to a safe drainage location away from the foundation of your home.
Gutters and Downspouts
Gutters are plastic or metal troughs attached to the edge of the roof that collect water runoff. The troughs direct the water downspouts that direct it to a safe drainage location. This prevents water from dripping down the walls of the home and pooling at the bottom, potentially causing water damage to the foundation.
The drip edge is a thin metal strip that protects the edges of your roof from water damage by directing water runoff into the gutters. This prevents the water from being absorbed into the edges of the shingles or seeping back onto the decking and causing rot around the edge of your roof.
The fascia is a visible board that sits against the roofline, and blocks moisture from entering the roofing system. The fascia also holds the gutters in place, and adds a smooth, even appearance to the edge of the roof.
Not every roof includes a soffit, but when they are needed it is for a good reason. The soffit is the underside of a roof that extends past the exterior walls of a home. Many times, soffits have built in vents which contribute to the overall roofing ventilation system to maintain good airflow throughout the roofing system.
Need Help With Your Shingle Roof?
If you are in need of a shingle roof replacement for your home, let Cenvar Roofing help you. We are a professional roofing company with experience in roof repairs and replacements on shingled roofs all over Virginia. Schedule your free estimate to start the process. We look forward to hearing from you!