Roofing Glossary

The highest point of a roof where two slopes meet.

Roofing material made from fibreglass or organic mat coated with asphalt and mineral granules.

The point where a roof slope meets a vertical wall, requiring flashing.

A decorative board fixed to the verge of a gable roof, covering the ends of roof timbers.

Horizontal strips fixed to rafters to support roof tiles.

The measurement between the top of one batten and the top of the next, determined by tile headlap.

A black, sticky petroleum-based material used in flat roofing and as a waterproofing agent.

A curved tile used to cover the hip of a roof, creating a rounded appearance.

A square or rectangular gutter, typically lined with lead or felt, built into the roof structure.

A roofing underlay that allows water vapour to escape while preventing liquid water ingress.

The top layer of a built-up flat roof system, often mineral-surfaced for UV protection.

A triangular mortar seal used at the junction between a roof and wall or chimney.

A channel cut into brickwork to receive flashing.

The side walls of a dormer window.

External covering material applied to walls or roofs for weather protection.

Traditional roofing tiles made from fired clay, known for longevity and distinctive appearance.

A tile designed to wrap over the verge edge, eliminating the need for mortar bedding.

Timber boarding laid with no gaps, used as a base for certain roofing materials.

A horizontal timber connecting opposing rafters, adding structural support.

Machine-made roofing tiles manufactured from sand, cement, and water.

Moisture forming when warm air meets cold surfaces in the roof space.

Vertical battens fixed over the membrane before horizontal tile battens.

A horizontal row of tiles or slates across a roof.

Flashing fitted over an upstand or step flashing to weatherproof the joint.

A short rafter that connects the hip or valley to the wall plate.

The structural surface onto which roofing materials are applied.

A structural extension from a roof slope containing a window.

A tiling method where each tile overlaps two courses below, common with plain tiles.

A vertical pipe carrying rainwater from the gutter to the drain.

A metal strip at the roof edge that directs water away from the fascia.

Mechanical fixing systems for ridges, hips, and verges that don't use mortar.

A ridge system using mechanical clips and seals instead of mortar bedding.

A prefabricated valley trough that doesn't require lead or mortar.

A system for finishing the roof edge at gables without mortar.

The lower edge of the roof that overhangs the wall.

The first row of tiles at the bottom of a roof slope.

A comb-shaped strip that blocks gaps at the eaves while allowing ventilation.

A component providing airflow into the roof space at the eaves.

Ethylene Propylene Diene Monomer, a durable rubber membrane used in flat roofing.

The board running along the roof edge at the eaves.

Waterproof underlayment installed beneath roof tiles.

Glass-reinforced polyester (GRP) used for flat roofs and valley linings.

Tapered timber strips creating a fall on a flat roof.

Material used to seal joints and prevent water ingress.

A roof with a pitch of less than 10 degrees, requiring waterproof membrane covering.

The triangular wall section at the end of a pitched roof.

The most common roof type with two slopes meeting at a central ridge.

Steel coated with zinc to prevent corrosion, used in fixings and flashings.

The exposed portion of a tile or slate visible when installed.

Glass Reinforced Plastic, a fibreglass material used for flat roofing.

A channel at the eaves collecting rainwater and directing it to downpipes.

A semi-circular ridge or hip tile, traditional in many UK regions.

The vertical overlap of tiles, ensuring water cannot penetrate between courses.

The external angle where two roof slopes meet.

The sloped triangular section at the end of a hipped roof.

A metal bracket at the base of a hip supporting the hip tiles.

The diagonal rafter forming the hip of a roof.

A roof with slopes on all four sides.

Special tiles designed to cover the hip of a roof.

A funnel-shaped collector at the top of a downpipe.

Material installed to reduce heat loss through the roof structure.

Single-lap tiles with side channels that lock together for weathertightness.

A short rafter that runs from the wall plate to a hip or valley rafter.

The craft of connecting timber elements in roof construction.

Horizontal structural members supporting a ceiling or flat roof deck.

The overlap between adjacent roofing elements ensuring weathertightness.

Traditional soft metal used for flashings, valleys, and flat roof coverings.

A horizontal piece of lead flashing at the front of a chimney or projection.

The technique of shaping lead around corners and complex shapes using tools.

The thickness classification of lead sheet, from Code 3 to Code 8.

Lead sheet used to seal junctions between roof and walls, chimneys, or other penetrations.

A raised joint in lead flat roofing allowing for thermal expansion.

A pre-formed lead collar for sealing pipes penetrating the roof.

Joining lead sheets using heat, either by burning or fusion welding.

A single-sloped roof attached to a higher wall, common on extensions.

A horizontal support above an opening in a wall.

A roof with two slopes on each side, the lower slope being steeper.

The exposed portion of a tile or slate between courses.

A waterproof layer in flat or low-pitched roofing systems.

Traditional bituminous felt with a mineral surface finish.

A roof with a single slope, also called a lean-to or shed roof.

A mixture of sand, cement, and water used in traditional ridge and verge bedding.

Corrosion of roofing nails causing tiles or slates to slip.

A short horizontal timber fixed between studs or joists for support.

Oriented Strand Board, an engineered wood panel used as roof decking.

The portion of the roof extending beyond the external wall.

An S-shaped interlocking clay or concrete roof tile.

A low wall at the edge of a flat roof or along a gutter line.

A glazing system using metal bars to support glass roof panels.

The angle of a roof slope, measured in degrees.

A flat rectangular tile requiring double-lap installation.

The mortar finish applied to ridge and hip tiles.

Corrugated or trapezoidal metal or plastic roofing panels.

A horizontal beam supporting rafters in larger roof spans.

A structural beam that supports the roof.

The portion of a rafter extending beyond the wall to form the eaves.

The horizontal line at the apex of a roof.

A horizontal timber at the apex to which rafters are fixed.

The vertical measurement from ground level to the roof peak.

Special tiles covering the ridge, traditionally bedded in mortar.

A ventilation system installed along the ridge allowing hot air to escape.

A traditional interlocking tile with a flat profile and raised roll.

The total surface area of a roof, including all planes.

A measure of how geometrically complex a roof is.

A window installed in the roof slope, also known as a skylight.

A prefabricated triangular frame supporting the roof structure.

A window fitted within the plane of the roof, such as a Velux.

Boards or membrane fixed to rafters beneath battens and tiles.

Temporary structure providing access for roofing work.

A concealed gutter built behind a parapet wall.

A small, flat piece of material laid in overlapping rows to cover roofs.

A tiling method where tiles interlock and overlap only one course.

A glazed opening in a roof providing natural light.

Natural stone roofing material split into thin, flat pieces.

A metal hook used to secure replacement slates without removing surrounding slates.

A tool for cutting nails when removing damaged slates.

The underside of the eaves overhang.

A ventilation grille fitted in the soffit board.

L-shaped metal pieces used with slates at abutments and valleys.

A short timber piece reducing the roof pitch at the eaves for a curved effect.

A vertical pipe, usually for soil or vent, penetrating the roof.

The first course of tiles at the eaves, often using shorter tiles.

Overlapping pieces of flashing that follow the slope of a roof against a wall.

Roofing material made from split stone, common in Cotswold buildings.

Timber or metal bands used to secure or restrain structural elements.

Traditional roofing using dried vegetation such as straw or reed.

An individual roofing unit, typically clay, concrete, or slate.

A wider tile used at verges to maintain bond pattern.

A metal clip securing tiles to battens, especially in exposed locations.

A tile with an integrated ventilation opening.

A triangular timber strip at the eaves lifting the first course of tiles.

Applying mortar to the underside of tiles for weather protection, now largely obsolete.

A prefabricated triangular roof frame manufactured off-site.

A projecting portion of a flashing dressed into a chase in the wall.

A strip of material beneath verge tiles providing a bed and weathering.

Secondary waterproof layer beneath tiles or slates, also called sarking felt.

A vertical surface where a flat roof meets a wall or raised edge.

The internal angle where two roof slopes meet.

Timber boarding supporting the valley lining material.

The lined channel running down a valley to discharge rainwater.

The diagonal rafter at an internal roof angle.

A membrane preventing moisture from entering the roof structure from inside.

A brand name commonly used to refer to roof windows in general.

Airflow through the roof space preventing condensation and rot.

The edge of a roof at the gable end.

Special tiles designed to finish the roof edge at gables.

A horizontal timber at the top of a wall receiving the roof rafters.

A roof construction with insulation above the rafters, keeping the roof space warm.

Small gaps in mortar allowing moisture to drain from behind.

High-quality natural slate from Welsh quarries, highly prized for durability.

Green-grey slate from the Lake District, traditionally laid in diminishing courses.

A metal used for flashings, gutters, and flat roof coverings, lighter than lead.