Roofing Terms Glossary

Asphalt roofing shingles are a type of roofing material made from fiberglass or organic matting that is coated with asphalt and granules.

A type of asphalt shingle that is thicker and more durable than traditional 3-tab shingles, with a dimensional appearance.

Tile roofing is a roofing material made of clay, concrete, or other materials that is durable, long-lasting, and has a distinctive appearance.

Slate roofing is a type of roofing material made from natural stone that is split into thin, flat shingles and installed in overlapping rows to create a durable, long-lasting roof.

Wooden shingles also known as wood shakes are made from split logs that are used as a roofing material for residential or commercial buildings.

Metal roofing is a roofing system made from metal panels or tiles, typically used on commercial or industrial buildings.

EPDM Roofing is a type of synthetic rubber roofing membrane that is commonly used on flat or low-sloped roofs.

TPO roofing is a type of single-ply roofing membrane made from thermoplastic polyolefin that is used on flat or low-sloped roofs.

PVC roofing is a type of plastic roofing membrane made from polyvinyl chloride that is used on flat or low-sloped roofs.

Built up roofing(BUR) is a type of roofing system consisting of multiple layers of roofing felt and hot tar or asphalt, which is then covered with smooth stones for extra protection. These are typically used for flat or low-slope roofs.

Modified bitumen is a type of asphalt-based roofing material that is reinforced with a polyester or fiberglass mat and installed in layers.

Roofing underlayment is a layer of material, such as felt or synthetic fabric, that is installed beneath the roofing material to provide an additional layer of protection against water infiltration.

Roof flashing is a material, typically made from metal or rubber, that is installed around roof penetrations or at the junctions of roof planes to prevent water infiltration.

Drip edge is a metal flashing installed along the edge of a roof to direct water into the gutters and prevent it from seeping into the building.

Ice and water shield is a self-adhesive membrane that is installed beneath the roofing material in areas prone to ice damming or water infiltration.

Ridge vents are a ventilation system installed along the ridge of a sloped roof to allow hot air to escape and prevent moisture buildup.

Soffit vents are a ventilation system installed in the soffit, or underside of the eave, to allow fresh air to enter the attic and prevent moisture buildup.

Gutters are a trough or channel installed along the edge of a roof to collect and direct rainwater away from the building.

Downspouts are a pipe or channel that carries rainwater from the gutters to the ground or a drainage system.

Skylights are a window installed in the roof to allow natural light into the building. Over time most seals around skylights leak and need to be repaired to prevent water damage to the interior of the property.

Chimneys are a vertical structure that channels smoke and combustion gases from a fireplace, stove, or furnace to the exterior of the building.

Roof crickets are a peaked structure installed at the junction of a roof and a chimney or other vertical structure to divert water around the structure and prevent water infiltration.

Roof valleys are the area where two sloping roof planes meet to form an inverted V shape, which can be prone to water infiltration.

Pitch is the angle of a roof, typically measured in degrees or as a ratio of rise to run. Roofs with a steep pitch are called steep sloped or pitched roofs.

Hip roofs are roof structures with four sloping sides that meet at a ridge, typically used on square or rectangular buildings.

Gable roof is a roof with two sloping sides that meet at a ridge, typically used on rectangular or triangular buildings. Gable roofs and hip roofs are the two most common types of roof structures.

Mansard roofs are a roof with two slopes on each of its four sides, with the lower slope steeper than the upper slope, typically used on buildings with multiple stories.

Flat roofs are a roof with little or no pitch, typically used on commercial or industrial buildings. These are also called low slope roofs.

Sloped roofs are a roof with a pitch or slope that is substantial enough to allow water to shed easily without a drainage system.

Roof decking is the surface of a roof that supports the roofing material, which can be made from materials such as plywood, OSB, or concrete.

Rake is the sloping edge of a gable roof that runs from the eave to the ridge.

A roof eave is the overhanging edge of a roof that extends beyond the walls of the building.

Fascia is a vertical board or panel that covers the edge of the eave and supports the gutter system.

Soffit is the underside of the eave that is exposed beneath the fascia, which can be vented to allow air flow into the attic space.

Ice dams are a ridge of ice that forms along the edge of a roof, preventing melting snow from draining off the roof and potentially causing water damage.

Roof ventilation is the process of circulating air through the attic or roof space to prevent moisture buildup, extend the life of the roofing system, and improve energy efficiency.

Standing seam is a type of metal roofing system where the panels are joined together at the seams, creating a raised, vertical profile.

R-value is the measure of the thermal resistance of insulation or other building materials, which affects energy efficiency and can vary depending on the material and thickness used.

Cool roofs are a roofing system designed to reflect more sunlight and absorb less heat than traditional roofs, which can help reduce energy use and mitigate the heat island effect.

Solar panels are a device that converts sunlight into electricity, which can be installed on the roof of a building to generate renewable energy.

Wind uplift is the force exerted by wind on a roof system, which can cause damage or even lift the roof off the building if not properly secured.

Green roofs are a type of roofing system that incorporates vegetation, soil, and drainage layers to provide a natural insulation and storm water management system.

Chimney caps are a cover installed over the top of a chimney to prevent water and debris from entering the flue and causing damage.

Roof coatings are a liquid-applied coating that is used to protect and extend the life of a roofing system, providing added protection against UV radiation, water damage, and other types of wear and tear.

A saddle is a small, peaked roof structure installed at the intersection of two sloping roof planes to divert water away from the joint and prevent leaks.

Roof penetrations are any opening in the roof plane, such as a vent pipe or skylight, which requires special flashing to prevent water infiltration.

Roof load is the weight of the roofing materials, insulation, and other components of the roof system, which must be supported by the roof deck and structural framing of the building.

Pitch pocket is a sealant-filled pocket used to seal around a roof penetration, typically made from metal or plastic.

Counterflashing is a metal flashing that is installed over the top of base flashing and into a vertical surface, such as a wall, to provide added protection against water infiltration.

Thermal shock is the stress placed on a roofing system due to rapid changes in temperature, which can cause materials to expand and contract at different rates and lead to cracking or other types of damage.

Vapor barrier is a material installed beneath the roof insulation to prevent moisture from penetrating into the building envelope.

The ridge is the highest point of a sloping roof where two roof planes meet.

A square is the unit of measurement used in roofing that equals 100 square feet of roofing material.

A starter strip is a strip of shingles or other roofing material installed along the eaves of the roof to provide a secure base for the first row of shingles.

Step flashing is a type of flashing used to seal the area around a roof penetration, such as a chimney or skylight, by alternating metal flashing with shingles.

A turbine vent is a type of roof vent that uses wind power to draw hot air and moisture out of the attic or roof space.

Underdrainage is a system of drainage channels or pipes installed beneath a green roof or other type of roofing system to direct excess water away from the roof and prevent water damage.

Single-ply roofing is a roofing system consisting of a single layer of membrane material, such as EPDM or PVC, which is typically used for flat or low-slope roofs.

A roof truss is a prefabricated roof support structure made from wooden or metal components, which can be quickly assembled on site to create a strong, stable roof frame.

UL listing is a certification given by Underwriters Laboratories, a third-party testing organization, to roofing materials that meet specific safety and performance standards.

A vent pipe is a pipe that extends through the roof to provide ventilation for plumbing or HVAC systems, which requires special flashing to prevent water infiltration.

A warm roof is a type of roofing system in which the insulation is installed above the roof deck, which can help to prevent heat loss and reduce the risk of ice dams.

A wind rating is a measure of a roofing system’s ability to withstand high winds, typically expressed as a number that corresponds to the maximum wind speed the roof can withstand.

A z-bar type of flashing used to seal the area around a roof penetration, such as a vent pipe or skylight, by creating a watertight seal between the roof and the penetration.

A roof parapet is a low wall or railing that extends above the roofline of a building, typically used to provide added safety or to conceal rooftop equipment.

A purlin is a horizontal beam or support used to provide added strength and stability to a roof frame, typically made from wood or metal.

Torch down roofing is a type of roofing system consisting of multiple layers of modified bitumen and fiberglass, which is installed using a torch to melt and bond the layers together, creating a durable, waterproof surface.

U-value is a measure of a roofing system’s ability to conduct heat, typically expressed as a number that indicates the amount of heat that is transferred through the roof.

A warm edge is a type of insulated roof edge detail designed to reduce heat loss at the perimeter of a flat or low-slope roof, which can help to improve energy efficiency and prevent ice dams.

A weep hole is a small opening or gap in a flashing or other roofing component designed to allow water to drain out of the roof system, which can help to prevent water damage and mold growth.

Zoning is the process of dividing a roofing system into separate areas or zones based on factors such as roof pitch, orientation, and exposure to wind or other environmental factors, which can help to optimize the performance of the roof system.

Attic ventilation is the process of allowing air to flow in and out of the attic space to prevent moisture buildup and heat retention, which can lead to energy loss and roof damage.

Cap sheets are the topmost layer of a multi-layer roofing system, typically made from asphalt or modified bitumen, which provides protection against weather and other external elements.

Roof decking is the structural layer of a roof that provides support for the roofing materials, typically made from plywood or other materials.

A joist is a horizontal beam that supports the roof deck and distributes weight evenly across the roof frame, typically made from wood or metal.

A scupper is a drainage hole or outlet on the side of a flat or low-slope roof that allows water to drain off the roof surface and into gutters or downspouts.

Roofing replacement is the process of removing and replacing an entire roofing system, typically required when the existing roof has reached the end of its useful life or sustained extensive damage.

Roofing repair is the process of fixing or replacing damaged or worn roofing materials, flashing, or other components to maintain the integrity and performance of the roofing system.

Roofing maintenance is the regular upkeep and inspection of a roofing system to identify and address any damage, deficiencies, or wear and tear, and extend the life of the roof.

Roofing systems are the combination of roofing materials, underlayment, flashing, and other components that form a complete roof assembly.

Roofing materials are any material used to cover and protect a roof, such as shingles, tiles, metal panels, or membranes.

Roofing codes are the regulations and standards established by local or national government authorities that govern the design, construction, and maintenance of roofing systems.

Roofing permits are documents issued by a local government authority that authorizes the installation or repair of a roofing system, typically required for new construction or major renovations.

Roofing inspections are a thorough examination of a roof to assess its condition, identify any damage or deficiencies, and recommend necessary repairs or maintenance.

A roofing warranty is a guarantee provided by a roofing manufacturer or contractor that covers defects in materials or workmanship for a specified period of time.

A roofing estimate is a document that outlines the cost and scope of work for a roofing project, typically provided by a roofing contractor or company.

A roofing company is a business that provides roofing services, such as installation, repair, and maintenance.

A roofing contractor is a professional who specializes in the installation, repair, replacement or maintenance of roofing systems.

Cedar shingles are a roofing material made of natural cedar wood that is durable and has a distinctive appearance.

Attic insulation is a material installed in the attic to reduce heat loss or gain and improve energy efficiency.

Eave vents are a ventilation system installed at the lower edge of a sloped roof to allow air to circulate and prevent moisture buildup in the attic.

Energy star is a certification program for energy-efficient products, including roofing materials, that meet certain performance standards.

Membrane roofing is a type of roofing system made of one or more layers of synthetic materials such as TPO, EPDM, PVC or modified bitumen.

Thermal emittance is the measure of a roofing material’s ability to release absorbed heat, typically rated on a scale from 0 to 1.

Solar reflectance is the measure of a roofing material’s ability to reflect sunlight and reduce heat absorption, typically rated on a scale from 0 to 1.

Roof slope calculations are the process of determining the pitch or angle of a roof based on its rise and run.

Skylight leaks are the water infiltration through a skylight, typically caused by improper installation or damaged flashing.

A roof leak is the unwanted entry of water into the building through the roof, typically caused by damaged or improperly installed roofing materials.

Condensation is the process of water vapor in the air turning into liquid as it comes into contact with a cool surface, such as a roof deck or insulation.

Thermal bridging is the transfer of heat through a building envelope, typically caused by materials with poor insulating properties.

A roof hatch is an access door installed on the roof to provide entry for maintenance and repair.

A gravel stop is a metal flashing installed along the edge of a flat roof to hold gravel in place and prevent it from sliding off the roof.

Roof drainage is the process of collecting and redirecting rainwater off the roof and away from the building.

Steep slope roofing is a roofing system with a pitch of greater than 2:12, typically used on residential buildings.

Low slope roofing is a roofing system with a pitch of less than 2:12, typically used on commercial buildings.

Fire rating is the measure of a roofing material’s resistance to fire, typically rated on a scale from Class A to Class C.

Vent pipe boot is a rubber or plastic boot that seals around a vent pipe to prevent water from entering the building.

Reroofing is the process of adding a new layer of shingles on top of an existing roof instead of completely replacing it.

Shingle tear off is the process of removing old shingles from a roof before installing new ones.

Roof snow removal is the process of removing snow from a roof to prevent damage from excess weight.

Roof flashing tape is a self-adhesive tape used to seal roof flashing to prevent water intrusion.

A roofer is a skilled tradesperson who specializes in roofing work.

Roof sheathing is the layer of boards or panels that are fastened to the roof rafters, onto which the roofing material is installed.