Glossary - General Pitched Roofing

Abutment: The junction of a roof surface with a wall or other part of the structure, which rises above it. Side or top.

Air Open: Allows the passage of air

Air permeable: Allows the passage of air

Air tight: Does not allow the passage of air

Angle ridge: Ridge formed by a sharp angle

Angle tile: Plain tile with a 90° angle used to cover external or internal angles in tile hanging, and fixed course by course together with the plain tiles, more commonly known as External or Internal angles.

Angular hip tile: Hip tile made to form an arris hip, laid across the cut ends of the tiles at the hip

Anti-capillary groove: Groove formed on the upper surface of a tile to prevent movement of moisture.

Apron flashing: Flashing used at junction of the upper edge of a monopitch or leanto-slope with a vertical surface. The top is tucked into a groove or joint in the brickwork, the bottom lapped over the upper edge of the slope.

Arris hip tile: Hip tile for use only with plain tiles, made to the correct angle for the roof pitch and laid course by course with the plain tiles

Barge board: Board fixed along the top edge of a gable against the brickwork, providing a straight edge for the tiles above

Back gutter: A gutter formed at the back of chimney or other penetration through a pitched roof

Battens: Horizontal timbers of small section on which tiles are laid. See also counterbattens.

Bedding: Mortar used to secure tiles or fittings at edges

Block end ridge: Ridge tile with one closed end

Boarded roof: Roof with boards fixed over the rafters, with roofing felt laid on top. (Scotland = sarking)

Bonnet hip tile: Hip tile for use only with plain tiles, curved to allow for its use on most pitches, and laid course by course with the plain tiles

Box gutter: a gutter with parallel sides

Broken bond: Tiles that must be laid so that the joints are staggered at each course

Built-up felt: Roofing felt laid as a series of layers, to protect flat roofs

Butt-joint: Straight joint between two units not overlapping

Capillary groove: Shallow groove on top or bottom surface of tile to prevent ingress of water by capillary action

Clip: Aluminium, steel or plastic device to secure tile to roof structure beneath

Cloaked verge: Verge formed using special tiles with legs to curl over gable end, to replace bedding

Cold roof: Roof with insulation at ceiling level and a ventilated void between the insulation and the roofing

Counter batten: Roofing batten laid from top to bottom of roof slope and underneath the normal battens

Course: Horizontal row of tiles

Cover flashing: Protection from rain ingress at edges and junctions, usually using lead

Cover width: Usable width of a tile on the roof.

Decorative ridge: Ridge tile with patterned top (ornamental ridge)

Dentil Slip: Decorative piece of clay/concrete designed to fit under ridge/hip tiles, bedded in mortar and used to break up deep thickness of mortar bedding

Diminishing courses: Courses whose gauge progressively diminishes from eaves to ridge.

Dormer cheek: Vertical side elevation of a dormer window, often covered with tile hanging

Dormer roof: Roof plane with at least one dormer window

Double course: Extra course of tiles placed underneath normal course for protection against water ingress, usually at eaves and top course with double lapped tiles

Double lap tile: Tiles designed so its lower edge laps tiles in two courses below

Double roll verge tile: Roof tile made with an extra raised part replacing interlocking channels for use at left hand verge only

Dry Fix: Mechanically fixing without the use of mortar

Dry ridge: Ridge line mechanically fixed without mortar

Dry verge: Verge formed without the use of mortar

Eave: Lower edge of a pitched roof

Eave comb: Component that fills the space under the roll of a roofing tile at the eaves, to keep out birds and vermin.

Eave filler: Device in plastic or foam, fixed under eaves tiles to fill voids created by tiles’ profiles

Eaves gutter: A gutter fixed at the eaves. A half-round eaves gutter is called a ‘Rhone’ in Scotland

Eave tile: Roof tile with different dimensions to allow it to be fixed under the normal eaves course tiles

Eyebrow: Dormer window constructed in a gentle curve like the shape of an eye

Fall: Slope of a flat roof or gutter

Fascia board: Board fixed to the rafter ends, wall plate or wall face at eaves.

Felt: Impermeable membrane laid over rafters before battens are fixed

Fillet, tilting: Strips, usually of wood, used at eaves or at open valley gutters for support

Finial: Decorative fitting at the end of a ridge, at the junction of a ridge/hip or at the top of a conical or pyramidal roof

Finial ridge: Ridge tile with finial fixed to it

Flashing: Strip of impervious sheet material that protects a joint, usually from entry of rainwater

Gable: Vertical wall end, above eaves level, enclosing the end of a pitched roof

Gable roof: Pitched roof that terminates at one or both ends as a gable, with verges

Gable tile: Tile specially made for use at a verge

Gas flue ridge terminal: Ridge tile incorporating a flue terminal for gas-fired appliances

Gauge (margin): Exposed part of the roof tile when laid on the roof. Equal to the distance between the top of one batten and the top of the next batten

Gutter: Any form of roof water channel

Gutter board: Board on which lining material is laid to form the sole of a gutter

Half tile: Roof tile made to half its normal width

Hanging tile: Plain tile used vertically as cladding

Head of tile: Top end of the roof tile normally hidden beneath the one above

HIP:

Hip tile: Segmental or angular tile to cover the cut ends of tiles at a hip. May be the same as, or smaller than, a ridge tile

Hipped end: Roof plane, usually triangular, bounded by hips at each side and eaves at its base

Hip iron: A metal strap bent to form a stop for the hip covering and screwed to the lower end of a hip rafter

Interlocking tile: Roof tile with longitudinal and possibly also transverse interlocking devices

Kiln: Oven for firing clay tiles

Knee tile: Curved plain tile for weathering mansard junctions. At least 3 courses of knee tiles are normally necessary.

Laced valley: Tiled valley where courses are not horizontal, each course being curved up to a tile-and-a-half laid aslant on a wide board. Gives the appearance of the 2 slopes being zipped together

Lap: The amount by which one tile overlaps another

Lay board: Board fixed across rafters to provide support for gutter linings or jack rafter.

Lead slate: Flashing used where a pipe or other sections passes through a roof. It comprises a base to course in withthe roofing and a sleeve to enclose the section.

Lean-to roof: Mono pitch roof with its upper edge against a wall.

Legged angle ridge: Angle ridge in which the lower parts of the two wings fall vertically

Mansard roof: Pitched roof that becomes nearly vertical half way down. After the French architect Mansart.

Mansard tile: Special roof tile designed to join the tiles on the upper and lower sections of a Mansard roof and bent to suit both pitches.

Mathematical tile: Tile for vertical cladding designed to create the appearance of brickwork

Membrane: See roofing felt

Mitred hip: Hip where the tiles are cut closely to an accurate line, with no cover above. Waterproofing takes place beneath the tiles by means of lead or metal. Only suitable for thin, flat tiles.

Mitred valley: Valley where the tiles are cut closely with no discernible gap. Waterproofing takes place beneath the tiles. Only suitable for thin, flat tiles

Monopitch roof: Pitched roof in one plane only

Monopitch ridge: Ridge tile with one vertical leg designed to cover a monopitch ridge,

Nib: Raised part on the underside of the tile, used to hook it on to the support, generally battens

Open eaves: Eaves in which overhanging rafters are exposed.

Open valley: Valley where the tiles are cut back so that the valley lining is visible in the space between the two roof slopes

Ornamental tile: Plain tile that has a shaped edge on the exposed portion

Ornamental tiling: Usually describes plain tiling with decorative tiles such as club or beavertail tiles.

Over fascia vent: Plastic unit fitting over the fascia board to provide ventilation, to guide water into the gutter and to prevent sagging of the underfelt

Pan: Trough of a single lap tile

Pantile: Traditional tile in the shape of an “S” lying on its side

Patina: Thin film of oxide or other metallic compounds forming on metal surfaces exposed to air.

Peg: Wooden peg to place through the nail holes of tiles without nibs, to allow them to be hung on to the batten

Peg tile: Traditional handmade plain tile with no nibs

Pitch: The slope (in degrees) of the rafters. Also used to identify parts of a roof e.g. the rear pitch as opposed to the front pitch.

Pitched roof: Sloping roof, the pitch of which is generally more than 10°. (At this pitch the tiles themselves may be less than 10°).

Plain tile: Small roofing tile (265 – 165mm) cambered but with no other features, usually with nibs and nail holes

RAFTER: 

Random slate roofing: Roofing of random slates laid in graduated courses, the width diminishing from eaves to ridge

Reinforced felt: Strengthened bitumen felt used under roofing tiles or roofing slates.

Ridge: Intersection at the top of two slopes in a pitched roof, forming its apex

Ridge board: Longitudinal structural member at a ridge.

Ridge capping: Protection from water ingress at a ridge, usually a ridge tile but may also refer to lead or other suitable material

Ridge vent: Ridge tile adapted to have a ventilating purpose in addition to its normal function

Roll: The raised part of a curved tile

Rooflight: Roofing tile or glass or translucent plastic.

Roofing felt: Impermeable membrane laid over rafters before battens are fixed

Ridge board: Longitudinal structural board at ridge normally found with a traditional cut roof.

Saddle: Piece of impervious flexible sheet material dressed to shape, fitted to provide weather protection.

Sarking: Impermeable construction under the tiles. In England refers to roofing felt but in Scotland refers to boarding with roofing felt above.

Sarking felt: See Roofing Felt

Secret gutter: Gutter formed under tiles butting closely against the side of a wall

Segmental ridge: Curved ridge tile whose arc is less than a semi-circle

Shingle: Wooden roof tile (can also refer to synthetic materials)

Side gutter: A gutter formed against an abutment and exposed to view.

Single lap tile: Tile designed to overlap both vertically and horizontally with adjacent tiles only

Slate: Traditional flat roofing unit, but can refer to concrete or clay products designed to emulate the appearance of traditional slates

Soaker: Small sheet, usually lead, shaped and inserted between roof tiles, slates or shingles at an abutment or at a hip or valley. Normally only for use with double lapped tiles.

Soffit board: Board, fixed to the feet of rafters, forming the underside of projecting eaves

Sprocket: A change in pitch from steeper to shallower, usually close to the eaves. Not recommended with interlocking tiles.

Square of roofing: 100 square feet of laid roofing. Not commonly used today

Staggered courses: Roof where the joints of the tiles are staggered from one course to the next. See Broken bonded tiles

Stepped flashing: Metallic strip (usually lead) used to prevent the penetration of water where a roof slope meets a wall

Stop end ridge/hip: End ridge or hip specially made with a blocked off end

Straight joint tiles/Straight Bond: Tiles that must be laid so that the joints of one course lie directly above the joints of the next course. (See Broken joint tiles)

Swept valley: Valley where the tiles are made or cut to a taper and sweep around the horizontals course.

Shoulder: One of two splays formed at diagonally opposite corners of a single lap clay tile

Tail of tile: Lower edge of the tile exposed to view from the ground

Tapered roll tile: Tile where the raised part is tapered outwards from head to tail

Tile-and-a-half: Tile made to one and a half times its normal width for use at verges in alternate courses when courses are staggered to produce a broken bond

Tiled valley: Valley in which the water flow is carried by the tiles themselves as opposed to the construction beneath them

Tilting piece: Woodwork beneath a tile to ensure its correct position

Top edge: Upper edge of roof surface finishing at a ridge or against a wall rising above

Torching: The practice of applying mortar to the underside of tiles on a roof to avoid driving snow or rain. No longer used since underfelt became standard practice.

Undercloak: Plain tiles, roofing slates or other suitable material fixed beneath battens at verges, on to which verge tiles are bedded.

Underlay: See Roofing Felt:

Valley: Where two roof slopes meet at an internal angle

Valley gutter: A gutter formed at a valley having sloping sides and exposed to view.

Valley tile: Tile made to an angle to form the centre of a valley

Valley trough: Purpose made concrete tile for weathering valley junctions when using interlocking tiles

Vapour Permeable:

Vent tile: Roofing tile with a weather protected opening to provide ventilation

Verge: Sloping edge of a pitched roof above a gable wall

Vertical tiling: Tiles used to create cladding on a wall

Warm roof: Roof with insulation directly beneath the roofing felt (or the boards if a boarded roof) i.e. where the insulation follows the line of the rafters.

Welt: Edge of piece of sheet metal folded to provide stiffness and a water check.

Winchester cutting: Method of cutting plain tiles, in vertical cladding, to finish against the sloping part (verge) of the pitched roof above, where the last two tiles in each course are splay cut.