Roofing Terminology You Need To Know

There is a lot of specialized vocabulary when it comes to roofing. Learning what all of the different terms mean can help you not only more easily converse with a roofer but also better understand what is happening with your roof during any roofing project. Plus, it will be harder for unscrupulous scammers to take advantage of you if you understand all of the roofing jargon already.

Parts of a Roof

Aggregate

Aggregate is a protective layer that sits on top of a roofing system. The aggregate layer can be made up of gravel, stone, rock, slag, or even crushed lava rock and gives a shingle its color. This layer helps to protect the roof from the sun’s UV rays because it provides both reflectivity and insulation.

Heat and age can cause the adhesive layer to break down, which lets the aggregate come off the base layer and reduces the shingle’s protective properties.

Apron Flashing

Apron flashing is an L- or V-shaped flashing that typically sits against a chimney. The purpose of apron flashing is to create a watertight barrier at a roof junction and to move the water towards the gutters.

Base Flashing

The purpose of the base flashing is to direct water towards the gutter so that it doesn’t build up on the roof. Base flashing is located at joints where the surface of the roof meets a vertical structure like a wall.

Batten Boards

Battens are thin strips of wood or metal that are fastened to a roof to support tile or metal roofs. They create a raised grid so the shingles, tiles, metal panels, or underlayment can be attached securely. On some roofs they also help with airflow under the roofing material, which can reduce heat and moisture problems.

Cap Flashing

Cap flashing goes over the top of base flashing as a seal for the flashing system to prevent water from getting in.

Cap Sheet

A cap sheet is a roofing material that looks like large asphalt shingles. It is commonly used on low slope or flat non commercial roofs such as carports and porches. It offers a more cost effective option compared to longer lasting choices like EPDM or TPO membranes.

Cricket

A small roof-shaped area often behind a chimney that directs water away from the valley. This adds an additional layer of water protection at this leak-prone area.

Decking

A roof’s deck is the wood later that sits between your home’s rafters and the roofing materials. Typically made from sheet OSB, particle board, or plywood, it serves as a medium that shingle nails attach to.

Dormer

A dormer is any kind of vertical framed projection, but is usually seen around a window.

Eaves

The eaves are the parts of the roof that extend out past the walls of the home. This overhang helps keep water away from the walls and foundation, especially if the gutters clog and overflow. The eaves also give space for vents that let air flow into the attic, which helps control heat and moisture.

Flashing

Flashing of any kind is a water-resistant barrier that is placed at joints and other less water-tight parts of a roof to ensure that water doesn’t enter the home.

Fasteners

Fasteners are small metal screws that are used to support your roof’s integrity against the weather.

Fascia

The fascia is the board that runs along the lower edge of the roof. Gutter systems are attached to the fascia.

Gutters

The gutters are the metal or vinyl tube system attached to the fascia of a home. Their purpose is to collect water that runs off the roof and direct it into downspouts so it can flow away from the home.

Hip

The hip is the angled line where two roof sections meet. The shingles used in this spot are thicker to handle weather in this vulnerable area, and designed to bend over the hip ridge (unlike regular shingles).

Overhang

The overhang is how far the eaves hang over the wall of the home.

Ridge

A ridge is the high point where two slopes meet. Typically, a ridge is the highest point on the roof and is a popular location for an air venting system (ridge vent).

Rafter

Rafters are a part of the system that supports the roof deck from within the house.

Soffit

Soffit is located on the underside of an overhang. It helps to keep moisture out of the attic.

Truss

The truss is the roofing framework that supports the roof.

Underlayment

The underlayment goes underneath the actual roof deck in order to protect it. The underlayment is a waterproof layer that helps to keep moisture out of the attic.

Valley

A valley on a roof is the opposite of a ridge. It’s where two slopes of a roof come together at their lowest point.

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Roofing Materials

3-Tab Shingles

3-tab shingles are a type of asphalt shingle that are designed with three “tabs” across the 12 inch width of each shingle. 3-tabs are often the most cost effective shingle option due to the ease of manufacturing but also lower cost materials used.

Architectural or Dimensional Shingles

Architectural shingles are a higher-quality type of shingles that have a fiberglass base and granules that are made up of ceramic-coated minerals. They have a more textured, eye-chatching style than traditional 3-tab shingles.

Asphalt Shingles

Asphalt shingles are the most popular type of shingles. They are made using asphalt, ceramic, felt paper, and fiberglass. Asphalt shingles typically cost less but also have a shorter lifespan than other shingle materials.

Bitumen

Bitumen is a viscous, black roofing material that comes from the process of distilling petroleum. It’s a waterproof material that is commonly used on flat felt and roll roofing.

It’s that is also used as a sealant for cracks in asphalt roads.

Dimensional Shingles

Dimensional, also known as architectural shingles, are textured shingles that have the appearance of being three-dimensional.

Metal Roofing

As the name implies, metal roofing is panels made from steel or alloy materials. It does have similar if not longer lifespan as shingles. And metal is available in both bold color options or organic styles that mimic shakes or tile.

Standing Seam (metal roofing)

Standing seam is a design feature of some metal roofs that adds rigidity to the panel, improves water-protection for mounting screws, and functions to as an aesthetic feature. It gets its name from the tall, vertical seams where panels interlock.

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Roofing Techniques

Blind Nailing

Blind nailing is a roofing technique that involves keeping the nails and other roofing fasteners hidden. This protects them from the weather and helps to protect the roofing materials.

Damp Roofing

Damp roofing is the process of treating a roof to resist water penetration when there is no hydrostatic pressure.

Roof Tear-Off

A tear-off is the complete removal of all roofing materials. Typically this is done as the first step in replacing a roof.

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Types of Roofs

Ballasted Roof

A ballasted roof is one that doesn’t have anchoring between the decking and the roof membrane. It is laid loose on the roof deck and held in place by layers of ballast, typically gravel or pavers. It can be a quick installation option for flat or commercial roofs.

Built-up Roof (BUR)

A built-up roof, also known as BUR, is typically a low-slope or flat roof that is made up of several layers. A BUR alternates layers of bitumen and fabric and is covered with a layer of aggregate.

Gabled Roof

A gabled roof is a type of roof in which two roof sections that slope in opposite directions meet at a point.

Mansard Roof

A Mansard roof is a style of roof in which all four sides of the roof have a slope and meet at a flat top.

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Roof Damage Examples

Alligatoring

Alligatoring is damage that can occur over time on a flat roof. It’s the process of the roofing material drying out and cracking giving the look of aligator skin.

Blistering

Blistering can occur on shingle roofs and is when bubbles appear on shingles. This is caused by gas or moisture within the shingle and can shorten a roof’s lifespan. It most commonly occurs on roofs that are poorly ventilated or over-heated.

Buckling

Buckling occurs in humid weather or on older roofs and is the process of asphalt shingles lifting up and not staying flat, giving the roof a wrinkled look.

Curling

Curling can occur when wind uplift pulls shingles up from where they are fastened on the roof.

“Nail Pop”

Nail pops are usually caused by the expansion and contraction that happen during a roof’s heat cycles, or from the roof becoming overheated because of lack of attic ventilation. As the wood expands, the nail can slowly work its way out of the deck and create a gap that lets water reach the attic.

Weathering

Weathering is the damage that occurs to a roof due to the effects of weather over time. It’s the gradual breakdown of the roofing materials as the roof reaches the end of its lifespan and needs to be replaced.