Abutments where a roof meets the side of a wall, dormer or chimney

Apex the highest point of the roof where the two slopes meet (see Ridge)

Arris hips hip tile normally ordered to match the roof pitch when using plain tiles

Bargeboard boards fixed to the underside of the verge at the gable ends

Batten gauge or just gauge; the measurement for the batten centres (normally measured top edge to top edge)

Block end ridge ridge tile with one end filled (often used with cloaked verge tiles)

Bonnet hips hip tile used in plain tiling with raised edge for pointing

Cloaked verge special tiles designed to turn down at the verge as an alternative to using mortar

Course row of tiles or slates going across a roof

Dentil slips small, rectangular sections of concrete or clay set into the ‘pan’ of a tile under a bedded ridge or hip tiles

Eaves draining edges of a roof (the part of the roof above the gutter)

Eaves fillers plastic sections (individual or in 1m combs) fixed on top of a fascia board to prevent birds and vermin from entering a roof

Fascia board timber or PVC board found at the eaves (behind the guttering)

Finial decorative end ridge tile with vertical feature (for instance, fleur-de-lis)

Fixed gauge tiles and slates designed to be laid at a fixed or tightly governed batten gauge

Flashings impervious strips fixed at junctions to make them weather-tight; lead is normally used for this purpose but other materials are also available

Half-bond (also known as broken bond) when tiles or slates are laid halfway across the course below

Headlap distance by which a course of slates or tiles overlaps the slate or tile below

Hips where two sloping roofs meet at an external corner of a house

Gauge see Batten gauge

Left-hand-verge tiles specially fitting tiles designed to finish off the left-hand side of tiling so that it is in keeping with the rest of the roof (for instance, double roll pan tiles)

Linear cover (also known as effective width) the visible width of a tile or slate once laid on a roof

Margin length of tile or slate left visible once it has been laid (equal to the batten gauge)

Mitre close, accurate cutting of materials at a junction

Overhang distance that the undercloak extends over the verge or the distance by which tiles or slates extend into a gutter

Pitch angle of the roof slope as measured from the horizontal

Ridge line running along the apex of a roof

Saddle flashing that covers a junction between two or more roof slopes

Sidelap distance by which one tile or slate is offset from the edge of the one below

Soakers small sections of watertight material (usually lead) used with slates and plain tiles, typically underneath a step flashing at abutments

Soffit area underneath the eaves between the underside of the fascia board and the wall

Sprocket shallow section at the eaves normally found on very steep roofs (such as steeples), designed to slow rainwater down before it reaches a gutter

Undercloak sections of slate/tile/fibre-cement strip used at a verge to provide a bedding key for the mortar at overhangs

Valleys line between two roof slopes at an internal corner of a house

Variable gauge tiles where the batten gauge can be adjusted (that is, reduced) to fit the rafter length

Verge outer edges of a roof area above the gable ends

Winchester cut decorative gable-end finish, normally done in plain tiles