Term

Description

Abutment

The junction of a roof surface with a wall, or any other structural feature, which arises above it.

Barge Board

A board fixed along the edge of a gable.

Batten

Horizontal small section timbers that are nailed to the rafters and to which tiles/slates are secured.

Back Gutter

A gutter formed in lead at the back of a chimney, or any other structure, which penetrates the roof to disperse water onto tiles/slates.

Cold Roof

A roof that has insulation laid horizontally at ceiling level and a void between the insulation and its outer roof structure and covering.

Course

A horizontal row of tiles or slates.

Dormer

Framed window unit, which projects through the sloping plane of a roof.

Down Pipe

Pipe which takes water away from guttering to drains.

Eaves

The horizontal, lower edge of a sloped roof - where the first course of tiles/slates are laid on the fascia board.

Fascia Board

The horizontal timber trim attached vertically at the eaves that covers the rafter ends, the wall plate or the wall face – the guttering is fixed to this and upon which the first course of tiles/slates are laid.

Felt/Underlay

Untearable bituminous or PVC sheet material, supplied in rolls and laid over rafters.

Flashing

Strip of lead, used at abutments, to stop water penetration. The ‘Code’ of lead means the thickness.

Gable

The upper portion of a sidewall, which comes to a triangular point at the ridge of a sloping roof.

Gauge

The length of tile/slate exposed after it has been installed. It equals the distance between the top of one batten and the top of the next.

Gutter

The trough that channels water from the eaves to the down pipes.

Headlap

The amount by which a tile/slate overlaps the course below it.

Hip

The meeting of two pitched roof surfaces, which meet at an external angle.

Hip Iron

A metal hook, which is secured to the roof structure to support the hip tiles and stop them from slipping.

Mortar

Sand & cement mix consisting of 3 parts sand to1 part cement.

Parapet

Low protective wall that extends above the roofline for support.

Pitch

Also known as ‘slope’ , is the measure of how steep a roof is. The pitch of a roof is a big factor in determining the kinds of materials that can be used and the longevity of the roof. Usually, a steeper roof will last longer due to its better draining capabilities.

Purling

Main structural roof support timber: usually situated half way up the roof span: to which rafters are nailed.

Rafter

The supporting framing timber, sloping from ridge to wall plate.

Raking Cut

A diagonal cut across courses of tiles/slates.

Ridge

The uppermost horizontal junction of two slopes forming the apex of a pitched roof.

Saddle

A piece of impervious flexible sheet material (usually lead) dressed to shape, fitted to provide weather protection.

Secret Gutter

A gutter former at an abutment and effectively hidden from sight.

Soaker

A small piece of sheet (usually lead), shaped and inserted between double lap tile or slates on the abutment between a roof slope and a vertical wall.

Soffit Board

A board fixed to the feet of rafters, which forms the underside of projecting eaves.

Undercloak

Fibre cement strip, fixed at the verge beneath the battens, onto which the verge tiles/slates are bedded.

Underlay

A layer of material acting as a barrier between the roof covering and the sub-structure (see felt).

Valley

The junction of two inclined roof surfaces at an internal angle to provide water run-off; channel to allow roof slopes at different pitches to join together and discharge water into gutters.

Valley Gutter

A visible gutter running down the valley.

Verge

A free end of a roof surface; for example that at the end of a gable or dormer.

Warm Roof

A roof that has insulation and a vapour barrier laid above or between its supporting structure (normally on the pitch of the rafters), and immediately below its weatherproof membrane.