Roofing Terms and Definitions: Roofing Terminology You Need to Know

If you’re about to start a roofing project, doing research, or already talking to a roofing contractor, you’ll definitely hear new terms. The problem is, there’s not much elaboration in articles or even when actually talking to someone in the roofing industry. 

This is not only confusing but also leaves you with even more research to do. Instead of looking up every individual term you read or hear, wouldn’t it be great if the most common roofing terms were in one place?

Here at Bill Ragan Roofing, we take extreme pride in educating homeowners like you. That’s why we’ll be giving you the most commonly used roofing terms and their definitions.

As you’re going through the article, there are hyperlinks to give you the option to dive deeper into each of the terms covered.

Roof decking (roof sheathing)

Roof decking is the wooden foundation that all your other roofing components are nailed onto.

There are two types of roof decking: sheet decking and plank decking. Sheet decking comes in either OSB or plywood, and plank decking comes in wooden planks. 

The main thing with roof decking (roof sheathing) is that you don't want it to get wet because it will rot, and you'll have to replace it.

Roof flashing

Roof flashing is a thin metal material that roofers install to direct water away from certain areas (walls, chimneys, roof valleys) of your roof. 

There are three different types of roof flashing (apron, counter, and step flashing), and you’ll have three different metals to choose from (aluminum, steel, and copper).

Roof underlayment

Roof underlayment is a synthetic or felt material that's installed directly over your roof decking or sheathing. 

It adds an extra layer of protection for your roof decking if water gets underneath your shingles. 

Ice and water shield

Ice and water shield is a waterproof membrane used to protect your roof from ice and water damage.

The 3 types of ice and water shield are granular/sand surface, smooth, and high heat. It needs to be installed on/around certain areas of your roof, like roof valleys, around penetrations, and on low slope roofs.

Rakes and eaves

Rakes and eaves refer to the edges of your roof. Rakes are the edge of a roof that runs at a slope.

Eaves are the edge of a roof that runs horizontally; think of it as the gutter line.

Roof facets

Roof facets refer to the different sections or the sides of a roof.

The more complex your roof is, the more facets it will have. 

Roofing square

A roofing square is a unit of measurement used in the roofing industry that determines factors like cost and the amount of material needed to complete a job. 

A square simply refers to a hundred square feet of roof area.

Prorated and non prorated

Prorated and non-prorated in roofing terms refers to the manufacturer's material warranty. 

A prorated material warranty means the material will lose value each year as it gets older. On the other hand, a non-prorated material warranty means the material keeps the same value as it ages.

Roof valleys and hips

Roof valleys are when two roof facets meet at a slope to form an interior angle. Valleys allow water to flow properly down a roof. 

A hip is when two roof facets meet at a slope to form an exterior angle. 

Gable

A gable is a triangular section underneath where two roof facets overhang a wall.

It's commonly used to refer to a popular ventilation spot, the gable end vent.

Drip edge

Drip edge is a metal component that's nailed to your decking at the edge of the roofline.

It's to keep the water running off of your roof from wicking back and getting your decking wet.

Fascia

Fascia is located right below the rakes and the eaves of your roofline.

It serves a decorative purpose, but it can also serve a practical purpose as your drip edge.

Soffit

A soffit is installed right underneath the fascia, where a roof overhangs a wall.

It's common for roofers to install an intake vent right where a soffit is located.

Dormer

A dormer is a section of roof, usually a window, that juts out and forms its own little small section of mini roof. 

Starter shingles

Starter shingles are a pre-cut row of roofing material installed at the eaves and rakes before the first course of shingles are installed over them. 

They also have an adhesive to ensure the first row of shingles are sealed to improve a roof’s resistance to strong winds.

Roof pitch

Roof pitch is simply the steepness of a roof. It's formatted in an X/12 fashion where X equals the rise, and 12 is the run. For example, a 4/12 pitch will rise 4 feet for every 12 feet of length.

Caulk

Caulking a roof refers to using sealant to fix common roof leaks. If a roof is caulked correctly, it should last a couple of years.

Roof cricket

A roof cricket is a sloped, double triangular structure that diverts water around chimneys and walls.

As water comes down a roof, it hits the roof cricket and splits down each side of the chimney instead of hitting a flat wall.

The different layers of a roof 

Now you know some of the most common roofing terms. While this article doesn’t cover every single term you’ll hear, it’s a great starting point for your roofing journey. 

To continue your roofing education, you’re ready to learn about the different layers that make up your roof. After all, your roof is a combination of different materials and components that come together to form a complete roof system. 

Because we want you to be the most informed homeowner in your neighborhood, we wrote another article breaking down the different layers of your roof system. 

The team at Bill Ragan Roofing has helped homeowners in the Nashville area with all of their roofing needs since 1990. Whether it’s for roof repairs or a full roof replacement, our customers are the most educated in the roofing industry after working with us. 

Check out The Different Layers of a Roof (& What You Need to Know About Them) to continue your learning journey about all things roofing.