Glossary of Terms
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Glossary of Terms [740KB]
Curtain Wall
Air sealThe internal gasket and curtain walling grid must be sealed to stop air and therefore water passing through the system from the outside
Curtain Walling
Aluminium grid incorporating glass and panels of various materials that overclads the building structure and hangs like a curtain
Deadload
The weight of aluminium and glass that the mullion has to support
Design windload
The pressure of wind acting upon the façade given in Newtons/m2. Can be positive or negative
Module
The sums of half the width of each panel either side of a mullion, not mullion centres
Mullion
Vertical bar that must withstand deadload and windload (does not support roofs) which is transferred back to the structure via brackets
Mullion drainage
Each panel within a curtain wall system is drained along the transom and down the mullion
Face cap
Aesthetic cover cap that fits over the pressure plate
Infiltration plug
Shaped EPDM plug that closes off the gap between mullions and transoms
Pressure equalisation
The principle of making a curtain wall system or window weathertight
Pressure plate
Plate that screws to the nose of the mullion and transom to retain the glass or panel
Purlin
Horizontal glazing bars within a slope glazed system
Rafter
Structural bar within a slope glazed system
Rainscreen
Allows air into the glazing cavity whilst keeping out as much water as possible
Simply supported
Mullion fixed at one end taking deadload and windload with a sliding fixing at the other taking windload only. Normally storey height bars
Span
Length of a mullion or transom between fixing points
Structural silicone glazing
Method of retaining glass by bonding the panel to an aluminium frame rather than using mechanical methods of retention i.e. pressure plates
Tandem span
Mullion spanning two storeys. Fixed at one end with a sliding fixing at the other and a sliding fixing at a point in between taking windload only
Transom
Horizontal bar that must withstand deadload and windload (does not support roofs) which is transferred back to the structure via connections to the mullions
Zone drainage
Each panel within a curtain wall system is individually drained at the end of each transom