The Structure of Your Roof

To get started, here are the 10 basic components of the structure of your roof:

1. Shingles

The role shingles play in the makeup of your roof is vital. There are 4 main functions: 

1. Aesthetics

Shingles are an important part of your roof. They are the first thing you see when you look at the roof of a house and depending on the color and style, your shingles can change the look of your house drastically. Aesthetically, the shingles are the most visually impactful aspect of your roofing.

2. Durability

This is a crucial element of the shingles of a roof. Durability of your house’s shingles affects the lifespan of your roof directly. When having a roof replaced or reinstalled, it’s important to do research on the type of shingle planning to be installed to make sure you are getting a quality product at an affordable price.

3. Utility

More than simply aesthetics, the color of your shingles impacts the utility of your roof. This is because due to the color chosen for your roof, you may have more or less impact from the heat. A lighter color will attract less heat than a darker color shingle. Of course, this also depends on the type of shingles used, but in most cases the color of your house’s shingles has an impact on the energy efficiency of your home. Depending on the hue of the shingle, this impact can be large or small. For a noticeable impact, choose a shingle that is Energy Star Certified.

4. First Line of Defense

Roofing shingles go through intense amounts of research, development, and engineering in order to stop water from being able to enter your home. There are many other parts of a roofing system, but shingles are what make up the majority of your roof and their most important job is to not allow water to run under their surface.

2. Synthetic Underlayment

This is the material that is laid over plywood sheathing to seal it from the weather damage. It is made from a synthetic material, typically either polymer or polypropylene (although there are a variety of other materials that are used as well). It is not always required per building code, but is certainly a good addition to the roof system. This underlayment can be a useful factor in the protection of unwanted and unwarranted extreme weather.

3. Ridge Board

The purpose of the ridge board is to join rafters at the top of a roof structure. A ridge board is at least 1” in width and length depends on the size of the run. This is the section at the peak of a roof that is where both sides of the roof meet in the middle. 

4. Rafters in the Structure of Your Roof

The rafters are the wood beams (sometimes metal) that support your home. They are the skeleton of your roof, making up the bone structure to be built upon by the other layers of the roof.

5. Collar Ties

Collar Ties prevent the rafter frames from separating. They are the section of the roof’s “skeleton” that aid in evening out the load of the roof, so things are evenly dispersed and well-balanced. Typically, the ties are on every other rafter about 48 inches apart; enough to ensure stability, and not overdo it.

6. Solid Plywood Decking

The most common type of roof decking is also referred to as roof sheathing. From the name you may be able to guess, but this is a solid layer of decking that is laid down before the many other layers.

 There are actually two different types of roof decking:

1. Plank Decking 

Plank decking is made up of rectangular wooden boards that are either sizes 1×6 or 1×8. These are often seen on older homes, and covered over with plywood when a roof is replaced today.

2. Sheet Decking

Sheet decking (or sheathing) are flat sheets of wood. There are two types of sheet decking that are used:

1. Oriented Strand Board, often referred to as “OBS”

2. Plywood. Plywood comes in different lengths and thicknesses, but most often roofers install 1/2″ thick sheets that come in 4’x8′ widths and lengths. Plywood is the most common type of roof sheathing installed today.

7. Ice and Water Shield

Ice and Water Shield is a product that you peel and stick onto the roof decking. This is an essential aspect of the roofing process that creates a water-proof barrier where ice and water are most likely to build up.

8. Seam Tape

Seam tape is a peel-and-stick type product similar to ice and water shield. It is not code in every state to include seam tape in a roofing system. But for states that it is required, seam tape is rolled out and stuck to the seams between the plywood sheets.

Seam Tape- The structure of your roof

9. Drip Edge

Drip edge is an angled piece of flashing that covers the plywood decking and runs over the fascia board as well. At Guaranteed Roofing, we opt for F8 drip edge in most residential and shingle roofing applications. The F8 drip edge has a 6” width over the roof deck and about a 1 ¼” width portion that runs over the fascia. The purpose of drip edge is to redirect water runoff away from the walls of the home and into gutters.

10. Ridge Vent

Although not necessary on all roofs, the purpose of a ridge vent is to allow air to escape from the pitched roofs. Ridge vents are only unnecessary if the roof already has adequate ventilation without it. When installed, they run the entire length of the roof at the top of the ridge.   

Want to Learn More? Check Out the Articles Below!

Every homeowner should have basic knowledge of their home, interior and exterior alike. For the purpose of this article, we will be discussing the basics of what      you need to know about your roof

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