Your roof has many parts, each with a specific job to keep your home or business safe and looking good. In this article, we’ll explain the main parts of a roof, what they’re made of, and how they work. This will help you talk to contractors and take care of your roof.
Measurement - Rise, Slope and Pitch
The rise, also known as the “slope” or “pitch,” is the measurement of the vertical rise of your roof over a horizontal distance, known as the “run.” The rise of the roof impacts the drainage, weather resistance, and curb appeal of your home. The run of the roof is usually measured as the height of the roof per 12 inches of run.
For example, 4:12 roof rise means that the roof increases in height by 4 inches for every 12 inches of horizontal distance.
Framework and Support
Battens
Also known as “roofing laths” or “furring strips”, battens attach to the rafters to create a surface for securing your roof materials. They are made from thin wooden, plastic, or metal strips and serve as anchor points for tiles, shingles, or other coverings. The spacing between battens depends on the type of roofing material you choose. They are most commonly used with clay, stone, or concrete tiles.
Rafter
Rafters are a traditional roof framing method, similar to trusses. Unlike trusses, which are pre-fabricated, rafters are built on-site and offer the ability to customize your roof. Rafters, joists, and purlins make the framework of your roof and ceiling. Typically crafted from wood (or metal for added strength), rafters can be either exposed or concealed, depending on the construction style.
Generally laid vertically side by side (in pairs), rafters are the beams that extend from your roof’s peak to the eaves. They run from one end to the other and support your roof deck and roof covering. Rafters connect to exterior walls and land on top of your roof’s ridge board.
Truss
Roof Surface Layers
Decking
Also known as roof “sheathing,” roof decking provides support and an anchor for roofing materials. Laid on top of the rafters, decking is typically made from half-inch plywood or strand board (OSB). It can be installed as plank sheathing or tongue and groove and is the foundation of your roof that reinforces the roofing system. A waterproofing material must be installed on top of the decking to prevent excess moisture from swelling or shrinking the roof decking and keep your attic well-ventilated.
Ice and water shield
Roof Covering
Your roof covering is the material used to protect your roof and contribute to its durability, aesthetics, and weather resistance. With tiles or shingles, each row of roofing materials is referred to as a “course.” Roof tiles are traditionally made from locally available materials and hung from the roof’s framework. Popular materials include:
- Asphalt Shingles – a popular, cost-effective choice for many homeowners. Made from organic, asphalt-saturated or fiberglass bases, they come in various thicknesses, dimensions, performances, and applications.
- Cedar Shake – this material is hand-split from a cedar log, giving it an irregular shape and a rugged appearance.
- Metal Roofing – more durable than most forms of roofing and resistant to fire, metal roofs can be installed over existing roofs (if local building codes allow it).
- Aluminum Roofing – the lightest metal roofing material, aluminum can be formed to fit a variety of architectural roofing structures.
- Roof Tiles (Clay, Concrete, Slate) – Clay tiles have been used for centuries and come in various colors and finishes. Heavier than clay, concrete tiles can be molded to imitate clay tiles and painted or colored for any aesthetic. Slate tiles are quarried and carefully split into layers for a distinctive appearance.
- Cool Roof – considered an energy-efficient roof, cool roofs are typically lighter colored materials or coatings and are designed to reflect more sunlight and absorb less solar energy. They’re known to lower the interior temperatures of a building and help to reduce energy costs.
- Green Roof – also known as a “living roof,” these roofs overlay growing vegetation on a roofing structure as a biodiverse habitat for local plants and animals (primarily birds and insects).
Standing Seam
A standing seam is part of metal roofing construction where concealed fasteners join metal panels together. A roof seaming machine seals the fasteners to create raised seams that run vertically along the panels. This technique protects your home from leaks and other water damage.
Underlayment
Installed directly on the roof decking (beneath the tiles or shingles), the underlayment is a thin cushioning and protective barrier against moisture and rot. Many types of underlayment membrane materials are available, including felt, rubber, reinforced fiberglass, and more:
- Eaves – typically used in colder climates, eaves membranes are self-sealing and protect the roof’s edge from ice dam formation.
- Felt – a type of tar paper made from polyester fleece infused with bituminous material or glass fibre, felt is the most common form of underlayment.
- Rafter – adds a layer of waterproofing to for your rafters.
- Synthetic – similar to felt and considered a high-tech alternative, adds waterproofing for the roof deck.
- Valley – provides additional moisture and rot protection against pooling water.
Edge and Perimeter Components
Eave
Also called a “roof edge,” the eave is the part of your roof that hangs over the sidewalls of your home. They create an overhang that is sometimes extended over walkways. Eaves run horizontally along your roof, serving as the lowest (and weakest) part of your roof where water drops to the ground. The primary function of eaves is to direct water away from your house’s exterior walls, making them the ideal place for gutter installation.
However, moisture buildup around these areas makes them prone to shingle or tile deterioration and metal corrosion. Check for damp spots, rot, or leakage along your eaves to prevent rot or internal water damage to your home.
Fascia
Gutters and Downspouts
Soffit
If you stand under the edge of your roof and look up, you’ll see material that covers the underside of the roof’s eave, which is called the soffit. Soffits are a finishing material that insulates your home and conceals your rafters and joints. It is located between the wall and fascia (or eaves). Common soffit materials include:
- aluminum,
- fiber cement,
- vinyl,
- and wood.
Vents/Ventilation
The space beneath your roof, typically an attic or loft, is a part of your home that protects the interior from extreme summer heat and winter moisture. Vents penetrate the surface of your roof and allow your roof to breathe. Roof vents can be passive, wind-driven, or electrically operated, and serve various purposes. Each type of vent requires specialized flashing.
- Gable vents – provide passive attic ventilation.
- Intake/Exhaust vents – allow air to flow through the roof, preventing condensation and roof material degradation.
- Plumbing vents – also known as “stack pipes” or “vent stacks,” these pipes ventilate the gases from your home’s plumbing system outside instead of inside your home.
- Ridge vents – provide ventilation at the peak of a sloped roof to allow warm and humid air to escape at the highest point of the attic or loft.
- Soffit vents – provide ventilation beneath the eaves to bring fresh air into the attic or loft space.
Waterproofing and Sealing
Flashing
Flashing is the part of your roof that acts as a barrier against water infiltration in the joints and seams. These also include metal inserts at the edges and connections between the home’s structure (eaves, walls, and piping). Traditionally made from lead, now it is typically made from thin galvanized steel, aluminum, and plastic.
Different types of flashing serve specific purposes.
- Chimney Flashing – is placed around the base of the chimney where it meets the roof to create a seal.
- Dormer Flashing – is applied where the dormer connects to the main roof.
- L Flashing – acts as a metal barrier to divert water away from intersections between two building surfaces (i.e. the roof and walls).
- Roof Edge – Also known as the “rake edge,” flashing is used along the edges of the roof (eaves, gables, and rakes) to protect perimeter borders.
- Skylight Flashing – is applied to around the edges of the skylight frame and roof.
- Vent Flashing – is applied around all roof penetrations, including vent pipes.
- Valley Flashing – is placed at the intersection where two sloping roof edges meet to divert water away from the seam.
- Wall Flashing – is used where the house’s vertical walls (including dormers and chimneys) meet the roof.
Drip Edge
Skylight
When integrated into a roof, skylights are a roofing component and interior lighting source. They come in all shapes and sizes, with long and rectangular being the most common. Skylights require tailored roof flashing to prevent leaks and maintain the roof structure.
Skylight
A chimney is a hollow, vertical roof projection that ventilates your home from your fireplace, stove, boiler, and more. Specialized flashing is installed between the roof and the chimney to create a water-tight seal.
Ridge and Ridge Tiles
The ridge is a structural element of the roof’s framework. It is the horizontal line at the highest point of your roof that connects the rafters to form the roof frame (often resembling a triangle). This triangle shape is formed where two sloping sides or gables meet to create the uppermost part of your roof, and the ridge is the line below the point.
Ridges are common structural elements of pitched roofs (including gambrel, gable, and mansard styles). Typically constructed from wood or metal and running the entire roof length, the ridge provides stability and support for your roofing structure.
When two roof sections connect, the joints leave an opening where water can flow through. These ridge gaps are covered with ridge tiles (specialized tiles) to keep water out. These tiles can also be used to accent your roof’s style.
Valley
A valley is where two roof sections meet to create a v-shaped channel that directs water off your roof. These pitched or sloped areas often have a valley rafter (like a gutter) underneath the valley to assist in water and debris run-off into the actual gutters.
Closed-Cut Valley and Closed-Woven Valley
There are two types of closed valleys where shingles or tiles extend across the valley from one (or both) sides of the sloped roof: closed-cut and closed-woven. Closed-cut valleys extend several feet from one slope to the adjacent slope. Shingles or tiles from the adjacent slope are cut parallel and short of the valley’s center. Closed-woven valleys have alternating or woven patterns of shingles or tiles extending from both sides of the valley.
Open Valley
In open valleys, roofing shingles are installed and then cut and sealed where they overlap the exposed metal flashing. The flashing remains visible and is often painted or coated to match the shingles.
Design
Abutment
A roof abutment is any part of a roof that connects to a wall positioned above it.
Dormer
Resembling a small room with its own roof, a dormer is a window extending out of a sloped roof. Dormers come in various sizes, allowing natural light and additional ventilation into your attic and loft spaces.
Gable
The area where two sides of a roof meet, forming a horizontal ridge at the top of a pitched roof, is called a gable. It’s the part of a sidewall (usually triangular) that reaches the roof’s ridge – created by connecting two eaves on a wall. The shape and detail of the gable depends on your type of roof structure. They can be at the front or back of a long building or on the sides if your building is wide. A gable roof looks like a triangle and is the most popular and simplest to build. While not technically a roof component, it’s a description of the sloped edges of your roof (also called rakes). Rakes can create an overhang (eave) or can stop flat.
Hip
A roof hip is the area where two or multiple sides of a roof slope downward toward the walls of your home from the roof’s peak. The hipped edge of a roof refers to the triangular section created at the junction where the sloping sides intersect. These intersections are covered by hip caps where a single layer of tiles or shingles covers the inclined angle.
Hipped roofs create an easy way for water to run off your roof. Hips come from two slopes meeting, four sloping sides, or multiple sections coming together to form hips (sometimes incorrectly called ridges) and valleys.
Remember that there is a difference between a “hip” and a “ridge”. A roof hip occurs when two roof surfaces intersect to create an exterior vertical angle. In contrast, a ridge is always a horizontal feature and constitutes the roof’s highest point.
Your Roof, Our Materials
For over 43 years, All Points Tile and Slate has served central Florida with quality roofing materials. Whether you’re a contractor or a homeowner, view our inventory to find what you need.
