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Building components

Wall Leaves & Backing

The distinct vertical layers that make up a wall — outer and inner leaves, the cavity between them, and the backing that supports what is fixed to the face.

8 entries in this category.

Overview

About this category

A wall is rarely one thing. It is commonly two or more leaves with a defined space between, each doing a different job, and the words for those parts — outer leaf, inner leaf, cavity, backing wall — describe positions rather than products. The same outer leaf may be brick, block or stone.

These entries explain what each leaf contributes and what depends on it. They do not say how wide a cavity should be, how leaves should be tied, or whether a given wall is adequate.

Boundaries

What this category covers, and what it does not

  • Covers the vertical layers of a wall build-up and the elements that back or subdivide them.
  • Does not cover wall SYSTEMS — cavity walls, solid walls, timber-frame walls and veneer-over-frame walls are building systems.
  • Does not cover wall ties, lintels or masonry units, which are published material entries.
  • States no cavity width, tie spacing, leaf thickness, bonding pattern or fire-resistance period.

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 sheetProfile or trimUnit or moduleVoid or cavity
Roles:Air controlDrainageFinishMoisture controlProtectionSeparationStructureSubstrateSupportWeather control

Entries

Wall Leaves & Backing 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.

Board or sheetBacking Wall →The wall behind a cladding or facade system that supports it, carries the control layers and separates inside from the construction outside.Profile or trimCavity Barrier →An element installed within a concealed cavity to interrupt it, so that the cavity does not form a continuous path through the construction.Unit or moduleInner Leaf →The inner masonry layer of a cavity wall, commonly carrying the floors and roof and forming the backing for internal finishes.Unit or moduleMasonry Pier →A thickened section of a masonry wall that stiffens it against sideways forces or carries a concentrated load.Unit or moduleOuter Leaf →The outermost masonry layer of a wall, exposed to weather and commonly separated from the structure behind by a cavity.Board or sheetSheathing Board →A board fixed across the face of a frame to close it, provide a continuous surface, and give the layers outboard something to bear on.Unit or moduleSolid Wall Body →A wall built as one continuous thickness rather than as separate leaves, which handles water by absorbing and releasing it rather than by draining a cavity.Void or cavityWall Cavity →The deliberate space between two leaves of a wall, which breaks the path water and heat would otherwise take across 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 →