Skip to main content
HELPERG Ecosystem
Build Design HubBuild Design Hub

Building components

Roof Carcass & Edges

The battens, boards and edge elements that finish a roof structure and prepare it to receive a covering.

13 entries in this category.

Overview

About this category

Between a roof's structural members and its covering sits a set of elements that are neither: battens that carry units, boards that close the plane, and the fascia, soffit and verge that finish its edges. Alongside them sit the things that interrupt the plane rather than continue it — a chimney passing through it, a dormer standing off it, a channel returning water to it — and the shaping that decides where that water goes. Each is a position in the roof, and each can be formed from several materials.

These entries describe what those elements do and what they depend on. They do not state gauges, laps, fixings, ventilation areas or falls.

Boundaries

What this category covers, and what it does not

  • Covers the elements between a roof's structure and its covering, and the elements that form, interrupt and finish a roof plane: battens, boards, eaves and verge, the projections and penetrations that cross the plane, and the shaping that sets where water goes.
  • Does not cover the structural members below — rafters, purlins and ridge boards are frame members.
  • Does not cover roof coverings, underlays or membranes, which are published material entries, nor roof ASSEMBLIES, which are building systems.
  • States no batten gauge, ventilation area, overhang dimension, lap or fixing pattern.

Browse

Forms and roles in this category

Descriptive labels for what is here. They are a way of reading the list, not a filter and not a ranking.

Forms:Board or sheetConveyance elementLinear memberProfile or trimUnit or moduleVoid or cavity
Roles:Air controlAttachmentDrainageInsulationMoisture controlProtectionSeparationStructureSubstrateSupportTerminationWeather control

Entries

Roof Carcass & Edges components

Every entry in this category. Each explains what the element is, what it depends on, and how it relates to materials, systems and junctions.

Linear memberCounter-Batten →A member run up the slope beneath the tile battens to create a drained and ventilated space above the underlay.Profile or trimEaves →The lower edge of a roof where it meets or oversails the wall, and where water, air and the roof's layers all have to be resolved.Board or sheetFascia →The board closing the ends of the roof members at the eaves, which commonly carries the gutter.Board or sheetSoffit →The board closing the underside of a roof overhang between the fascia and the wall, commonly carrying eaves ventilation.Linear memberTile Batten →A small horizontal member fixed across rafters that roof covering units hang on or are fixed to.Profile or trimTilting Fillet →A wedge-shaped member that lifts the first course of a covering, or eases a sharp change of angle beneath a membrane.Profile or trimVerge →The sloping edge of a roof at a gable, where the covering stops against open air and must be held down and weathered.Conveyance elementBack Gutter →A channel formed across the high side of a chimney, kerb or abutment, collecting water running down the slope and leading it out to both sides.Unit or moduleChimney Stack →The masonry construction that passes through a roof and continues above it, weathered on every face and interrupting every layer of the roof it crosses.Unit or moduleDormer Cheek →The vertical side of a dormer, standing on the roof structure and closing the dormer between its face and the slope it projects from.Linear memberFirring Piece →A tapered length fixed over a flat roof's joists so the deck laid on it falls toward the outlets while the structure beneath stays level.Void or cavityOutlet Sump →A local recess formed in a roof or deck build-up around an outlet, so the surface falls into the outlet from every direction rather than merely arriving near it.Unit or moduleRoof Walkway →A defined route across a roof for access to plant, outlets and openings, formed so that traffic acts on the walkway rather than on the covering beneath it.

Related reference libraries

Components are what materials become and what systems are made of. The three libraries answer different questions and are kept deliberately separate.

Materials Library →Building Systems →