October 26, 2017

A – D

A – D



The scientific study of sound especially its generation, transmission and reception.

Air Gap
Air space between the panes of glass in an insulating glass unit (IGU).

Air Infiltration
Term used to describe one of the tests required by AS2047. The window shall not exceed air leakage requirements as specified for either air conditioned buildings or non-air conditioned buildings.

Annealed Glass
Glass which is cooled gradually during manufacture in an annealing operation to reduce residual stresses and strains which can be produced during cooling. This is the ordinary glass used in windows.

Arched Head
A curved and glazed portion of the window located at the head of the window.

An inert, nontoxic gas used in insulating windows to reduce heat transfer.


A moulding or stop used to hold glass or panels in position. It can be aluminium, timber, rigid PVC or flexible PVC.

Bottom Rail
The bottom horizontal sash bar.

Brick Opening
Opening size measured between the outside brick faces.

Brick Veneer
Construction where the outside skin of the wall is brickwork and the inside wall is timber stud frame.

The window frame is installed as the building progresses. Window fitted into the wall as the wall is being built.

Butt-Joined Glazing
Installation of glass products where the vertical glass edges are without structural supporting mullions.


The space between the panes of glass in an insulating glass unit (See also Air Gap).

Cavity Brick
A type of construction where both the outside and inside skins are brickwork.

Cavity Closure

An applied section usually fitted to the inside of the jamb section that extends the frame depth so that the window section spans the cavity.

Chamfer Board
A term used in Queensland to describe their own type of weatherboards.

(See Glazing Channel)

Colonial Bars
Horizontal and vertical bars fitted across window panes to give ‘period’ style effect.

Colonial Window
A window that is configured with horizontal and vertical bars to recreate the early colonial style of windows. It can be achieved with applied bars adhered to the glass or individually glazed.

Coupling Mullion
A vertical coupling member used to join two windows together.

Cover Plates
Usually vertical cover plates used to join two windows together. Not a coupling mullion. Used with or without a pipe staunchion.

Curtain Wall
A non-load-bearing window wall that is not a panel wall.


Daylight Opening
The clear daylight size that is visible through a glazed window pane.

Dehydrating agent within hollow spacer frames to absorb moisture from air within IGUs.

Double-Glazed Unit
Two panes of glass separated by an air or gas space designed to improve insulation against heat transfer and/or sound transmission. The air between the glass sheets is dried and the space is sealed, eliminating possible condensation and providing superior insulating properties.

A small, round wood unit with shaped ends, provided with a glue groove for joining together stiles and rails.

Drainage Slots
(See Weep Holes)