Abutment
An intersection of the roof surfasce and a part of the structure that rises above it.
Apex
The intersection of two or more roof slopes at the highest position on the roof
Bargeboard
A component fixed along the edges of a gable and covering the ends of the horizontal roof members.
Batten
A small-section timber member of minimum size 38 x 38 mm, used to support a roof covering of tiles or slates.
Bearing
A structural support, usually a wallplate on a load bearing wall, that occurs at the points of roof truss/beam/rafter.
Bedding
The settings and pointing of tiles and fittings in mortar.
Bedding pieces
Small pieces of broken tile that are used to reinforce areas of bedding where excessive mortar shrinkage can occur.
Boards
Lengths of flat timber (usually tongue-and-grooved) that are nailed to the rafters to form a ceiling and act as a support for the underlay.
Brandering
Small section timber members of minimum size 38 x 38 mm, used to support a fixed ceiling. Brandering is usually fixed directly to the underside of the bottom truss chord or rafter.
Chord
The main memebr that forms the outline of the truss.
Cleat
A specially formed strip of corrosion-resistant material, usually of the same material as the valley liner that is used to hold the valley liner in place.
Coastal Area
Those areas between the coastline and an imaginary line 30km inland, parallel with the coastline, or the top of the escarpment or watershed of the first mountain range inland, if these are less than 30km from the coastline.
The entire area of jurisdiction of any local authority whose area is cut by the line demarcating these coastal areas is taken as falling within the coastal area.
Concealed gutter
A formed channel, manufactured from a suitable, corrosion resistant material, that is overlapped by tiles and shaped to form a watertight joint at abutments in conjuction with cover flashings.
Counter battens
Timber members of small section fixed at right angles to the direction of the battens onto which tiles are fixed.
Crest
The upper part of the cross section of a roofing tile or profiled sheet when laid.
Eaves
The overhanging lower edge of a roof slope.
Eaves closure piece
An accessory, incorporating a drip that closes the corrugations of a profiledsheet at eaves level.
Facia board
A member that is fixed to the rafter ends, the wallface or the wall plate immediately below the eaves.
Fastener
A bolt with a nut, or a screw.
Flashing
A strip of flexible impervious material that is used to exclude water from the junction between a roof covering and another part of the structure.
Flute
The upstand between the troughs of box-ribbed sheeting.
Gable
The part of the wall above the general level of the eaves at the end of a ridged roof or of a patially hipped roof which encloses the end of a pitched roof.
Gutter
Any form of rain-water channel at eaves, verges and abutments.
Head lap
The distance by which one course of tiles overlaps the course immediately below it.
Heel joint
The pointon a truss at which the top and bottom chordsintersects, or where the first vertical web intersects with the bottom chord in stub ended trusses.
Hip
The sloping intersection of two inclined roof surfaces that meet at a salient angle.
Hipped roof
A pitched roof with hipped ends.
Lateral
Sideways with respect to the truss or other member under consideration.
Metal tile
A profiles metal tile that relies on the tile or sheet section to span between battens.
Monoridge
The intersection of a single roof slope and a vertical face at the highest part of the roof.
Mortar
A mixture of mortar sand, cement and inorganic pigment (optional) used for bedding tiles, ridges and fittings.
Mono pitched roof
A roof sloping in one direction only.
Nail-plate
Galvanized steel plate punched to form a nail pattern integral with the plate, which is used as a structural connector.
Pan
The flat portion between the ribs an a ribbed-through/standing seam sheet.
Pitch
The angle of inclination to the horizontal of the rafters, or of the surface on which tiles are laid.
Pitched roof
A roof, the slope of which is generally higher than 10 degrees to the horizontal.
Profiled sheet
Sheeting that has longitudinal ribs or corrugations.
Purlin
A horizontal member attached to, and placed perpendicular to the rafter in order to support the roof sheeting materials.
Purlin beams
Horizontal members which span between walls as the main roof structure and which act also as purlins to support the actual sheeting materials.
Rafter (Top chord)
A horizontal or inclined member that establishes the upper edge of a truss (top chord).
Runner/Binder
A continuous bracing member that runs the length of the roof to provide lateral stability for web members or chords of trusses in conjunction with triangulated cross bracing or other stiffener.
Softwood timber
Timber derivedfrom coniferous trees grown in South AFrica
Tie beam (Bottom chord)
A horizontal or inclined member that establishes the lower edge of a truss (Bottom chord)
Truss
A rigid structural component, assembled from timber members and node connectors (nail-plates or bolts), which form a pattern of triangles.
Truss spacing
The distance between two adjacent trusses.
Wall plate
A strip of timber, laid on top of walls to levelthe underside of rafters and trusses.
Web
A member that joins the top and bottoms chords to form triangular patterns that gives trussaction.
Source: NHBRC Home Building Manual
