The Anatomy of a Roofing System: Why Every Layer Counts

The Anatomy Of A Roofing System: Why Every Layer Counts

Most people understand that the human body consists of more than just the outer appearance (e.g., skin, hair, eyes, ears, nose, mouth, etc.). Although you cannot see another person’s internal organs or other systems, you understand they exist. The same analogy applies to roof layers. The outside layer of the roofing system is the visible surface material (typically asphalt shingles, wood shakes, or clay tiles). Under that layer, several sublayers exist, each serving a crucial function. These layers must work harmoniously to ensure a roofing system performs optimally.

The Visible Roof Layers Of An Asphalt Shingle Roofing System

Visible Layers: 1. Hip & Ridge Shingles 2. Ventilation 3. Roofing Materials 4. Starter Strip Shingles 5. Flashing

Wherever two slopes meet on a roof, hip, and ridge capping ensures a layer of sturdy outer protection to keep water from penetrating a particularly vulnerable area.

Ventilation connects the outside air with the home’s interior. Most roofs have ridge vents at the peak to allow hot air from the attic to escape outside naturally and efficiently.

The word “roof” typically refers to visible materials, like asphalt shingles. However, many homes have other types of roofing (slate, metal, clay) instead.

This feature consists of a highly adhesive, specially designed, pre-cut row of shingles adjacent to a roof’s edge. These shingles help increase a roof’s wind resistance.

Generally, flashing is manufactured from metal (aluminum, copper, or steel). It keeps water from penetrating at particular junctures (chimneys, vents, valleys, eaves, etc.).

The “Hidden” Roof Layers Beneath The Outer Surface

Generally, the underlayment is made from asphalt-saturated felt, rubberized asphalt, and non-bitumen synthetic material. Roofers sandwich it between the roof decking and the shingles to offer additional protection from outside elements (namely, moisture). The underlayment is added to the entire roof deck. It allows water vapor to escape while stopping liquid water from touching the wood-based decking, where wood rot will occur.

This waterproof membrane protects your roof from ice (in the form of ice melt) and water infiltration. If moisture penetrates the outer roofing surface, this barrier protects your roof decking (generally wood-based) from damage. Specific areas of your roofing system need effective shields, including roof valleys. Low-slope or flat roofs are particularly vulnerable to moisture intrusion and benefit from a barrier.

Classified as “metal flashing,” drip edges prevent water from reaching your fascia or seeping underneath roofing components (such as vents and gutters). Without drip edges, moisture will penetrate through the tiniest gaps, causing fascia boards and roof decking to rot. Most building codes require drip edge flashing. Unfortunately, many roofers omit or improperly install drip edges. A homeowner may not realize this problem until it’s too late.

Generally, this roof layer is made from plywood or OSB (oriented strand board). Decking must be sturdy enough to support any layers placed over it and withstand outside forces (wind, rain, snow, etc.). In some cases, reinforced or higher-grade decking may be necessary, especially if the roof must survive dense roof materials or significant snowfall.

A home’s attic insulation prevents heat loss through your roof and helps promote energy efficiency. Consequently, a well-insulated home reduces heating and cooling consumption. It also contributes to reducing the possibility of ice dam formation. Many kinds of attic insulation exist. Each one has a specific purpose. Homeowners are encouraged to hire a knowledgeable roofing professional to install the right insulation type and amount.

Framing is the innermost layer of the roofing system. It lays the foundation for the layers above it. Without structurally sound framing, a roof will incur serious challenges over time. Framing includes the trusses and joists (generally manufactured from wood as beams or studs). Reinforcement of junctures that connect the framing is necessary for its stability. Having the appropriate design and executing the construction of it is essential.

Hidden Layers: 1. Roof Underlayment 2. Ice & Water Leak Barrier 3. Drip Edge 4. Roof Decking 5. Attic Insulation 6. Framing

Hiring A Knowledgeable Roofing Contractor To Manage Every Roof Layer

For homeowners in Northeastern Illinois, including Greater Chicago, 3JM Exteriors delivers unsurpassed residential roofing services. We understand the intricate nature of a roofing system. No two roofs are the same. However, every roofing system possesses a series of layers that require functioning as one to perform optimally. If one layer fails, the entire roofing system could be jeopardized.

Contact 3JM Exteriors today with questions or concerns about your existing roofing system. We’ll dispatch a knowledgeable representative to assist you in identifying any problem areas and providing helpful information and permanent solutions. We don’t recommend temporary patchwork answers. Your roof needs to protect your home for the long haul, and we help ensure that positive outcome.

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