Roofing Glossary

A light duty exposed fastener panel used almost exclusively in residential construction.

An exposed fastener panel consisting of 4 ribs spaced 9" apart.

Lightweight, corrosion-resistant metal roofing material ideal for coastal environments.

A design feature preventing water from siphoning into panel overlaps.

An electrochemical process that enhances corrosion resistance and appearance of aluminum.

Foam rod inserted into joints before sealing to control the depth of the sealant.

Metal plate at the base of a structure to which framing or roofing components are attached.

A raised strip used to support roofing panels or tiles.

Minimum radius a metal panel can be bent without cracking.

A concealed roof gutter system typically built into the roof structure.

A type of rubberized sealant used on metal panels. Typically sold in rolls of 40-50 feet long.

A metal covering over joints or seams to prevent water infiltration.

A coating’s ability to resist color fading and surface chalking over time.

A small metal piece used to fasten panels to the roof deck without penetrating them.

Continuous application of coatings to rolled metal sheets before fabrication.

Fastener system hidden beneath the roof surface for a cleaner appearance.

Roofing that reflects more sunlight and absorbs less heat, improving energy efficiency.

Durable, corrosion-resistant roofing material known for its natural patina.

Permanent static weight on a roof, including the structure and any fixed materials.

The structural surface, usually wood or metal, to which the roofing material is applied.

Expected loads (dead, live, wind, etc.) that a roof system must support.

A standing seam profile where seams are folded twice for additional strength.

A vertical pipe that carries rainwater from a gutter to the ground.

The lower edge of a roof that overhangs the building’s wall.

Metal flashing installed along the eave to create a finished appearance.

Metal flashing installed at roof perimeters to secure and protect edges.

Applying a zinc coating to steel via an electric current to prevent rust.

A device allowing movement caused by thermal expansion/contraction.

Category of metal roofing where the fasteners that attach the roof to the structure remain exposed to weather throughout the life of the roof. Also sometimes referred to as "through-fastened panels."

A vertical finishing edge connected to the ends of rafters, trusses, or gutter systems.

Measurement of the force needed to pull a fastener out of a substrate.

Joining metal roofing panels together on-site, typically by mechanical seamers.

An extended lip or edge used to attach or strengthen metal components.

Metal pieces that redirect water away from critical areas like chimneys or vents.

A method of attaching a standing seam panel using a stand-off clip to attach to the structure. This method allows the roofing system to 'float' so thermal changes do not put additional stress on the panels.

Narrow strips of wood or metal providing a level surface for attachment.

Steel coated with aluminum-zinc alloy, offering superior corrosion resistance.

Steel coated with a layer of zinc to prevent corrosion.

Measurement of metal thickness; lower numbers indicate thicker material.

Horizontal structural member between columns, supporting wall panels.

A channel along the eaves to collect and divert rainwater.

A manual tool used to fold and lock seams in metal roofing.

Folding the edge of metal back onto itself for strength or safety.

Roofing panels with pronounced ribs for structural strength and water shedding.

External angle formed where two sloping roof planes meet.

Trim covering the hip of a roof to protect and seal the joint.

Ice buildup at eaves that can block drainage and force water under the roof.

Roof’s ability to withstand impact from hail or debris.

Type of standing seam panel where the seams snap together.

Seam folded downward rather than upward, often for aesthetics or waterproofing.

A trim shaped like a “J” used to cover and protect cut panel edges.

Preformed flashing used to seal around pipe penetrations.

A high-performance fluoropolymer resin used in durable roof coatings.

Metal flashing at the roof-to-wall intersection that diverts water away from walls.

Overlapping joint between two metal panels.

Temporary weight (snow, workers, etc.) that a roof system must support.

A roof with a pitch typically less than 3:12.

Standing seam profile created by folding metal panels together using special equipment.

Waterproof layer installed beneath metal roofing to provide extra protection.

Installation of a new metal roof directly over an old one.

Natural appearance of metal after rolling or extrusion, without added coatings.

The lowest slope recommended for a particular roofing system, typically per manufacturer guidelines and warranties.

Blocking installed to provide a secure base for fasteners.

Type of standing seam panel where one side of the panel has a perforated or pre-punched strip. These panels are attached directly to the roof deck.

A panel designed to fit within or overlap with another for secure assembly.

A ridge cap that seals the roof peak without providing ventilation.

Visible waviness in flat areas of metal panels due to stress or installation.

Portion of the roof extending beyond the wall line.

Specific shape and dimensions of a metal roofing panel.

PBR is an initialism for Purlin-Bearing Rib - a type of exposed fastener roofing panel used primarily on Pre-Engineered Metal Buildings.

Pre-engineered metal buildings (or PEMBs) are buildings that are manufactured and designed with minimal use of materials and maximal flexibility. These buildings are typically purchased as kits and can be erected nearly anywhere in the world.

Any item that passes through the roof, such as vents or skylights.

A structural roofing member typically bearing on a beam or rafter. Typically, an uneven Zee shape is present in modern PEMB design. When the same shape is used for wall framing, it is called a wall girt.

A tool or system that speeds up field-seaming of standing seam panels.

Semi-circular arched roof often used for pre-engineered metal buildings.

Exposed-fastener metal roofing panel commonly used in commercial projects.

The ability of a roof surface to reflect solar radiation.

The horizontal line where two sloping roof planes meet at the top.

Metal covering used to seal and protect the ridge.

Raised metal frames around roof penetrations like HVAC units.

The incline of a roof, expressed as a ratio of rise to run in inches.

Method of installing a new roof without removing the existing roof.

The joint where two roofing panels meet.

Waterproof membrane that adheres directly to the deck without fasteners.

A fastener with a drill bit tip that eliminates pre-drilling.

A window installed in a roof to admit natural light.

Another term for roof pitch, the steepness of the roof.

Category of metal roofing wherein a panel profile includes vertical seams and fasteners which are concealed from weather.

A structural member installed on top of an existing roofing system to allow for a roof-over or recovery.

Path where heat easily flows through a roof assembly, reducing insulation efficiency.

The tendency of materials to expand and contract with temperature changes.

Metal roof system where panels are attached to the structure with exposed screws.

Finishing pieces that cover edges, corners, and transitions on a roof.

A protective layer installed beneath the roofing material to shield against moisture.

Ability of a roofing material or coating to resist degradation from ultraviolet light.

The internal angle formed by two sloping roof planes meeting.

Metal flashing installed in valleys to direct water off the roof.

Pipe that vents air from the plumbing system, extending through the roof.

Decorative paneling, sometimes metal, installed on lower sections of walls.

A roof’s ability to allow rain to flow quickly off the surface.

Small hole that allows accumulated moisture to drain.

Ability of a roof system to resist wind pulling it away from the deck.

Structural bracing using crossed metal members to resist lateral forces.

The amount of stress at which a material begins to deform permanently.

A shaped closure used under roof panels to seal gaps against weather.

An initialism for Zinc-Alloy Cap fasteners. These are upgraded fasteners with a cap designed for long life in extreme weather conditions.

Steel coated with a zinc-aluminum alloy for enhanced corrosion resistance.