Glassary - I

I.G.U.:
Insulating Glass unit.

Impact performance:
the impact resistance of a safety glass when tested according to BS 6206. See also Technical Bulletin Glass and Safety

Impact resistance:
the classification according to BS 6206. See also Technical Bulletin Glass and Safety.

Impact resistant:
a euphemism for being a safety glass.

Impact safety:
an alternative term to impact resistance.

Inclined glazing:
glazing which is either horizontal or sloping up to 750 from the horizontal. Glazing within 150 of vertical is defined as vertical glazing.

Incombustible:
an alternative word for non-combustible.

Infill panel:
depending on the context, this could mean:

  • an alternative term for spandrel panel or
  • a panel underneath the handrail in a barrier.

Inner glass:
see inner pane.

Inner leaf:
see inner pane.

Inner pane:
the pane on the room side of an insulating glass unit or double window.

Installation:
depending on the context this is either:

  • the act of glazing, or
  • the finished glazing.


Insulated panel:
a spandrel panel with insulation in the form of organic foam or mineral wool attached to the rear face to lower the U value.

Insulating glass:
a fire resistant glass, which gives both integrity and insulation for a specific period of time greater than 30 minutes. The Pilkington Pyrostop™ range of products is insulating glass. Do not confuse insulating glass with insulating glass units.

Insulating glass unit (or I.G.U.):
Commonly known as a double glazing unit (D.G.U.) a construction consisting of two or more panes of glass spaced apart with spacer bars to form a cavity between the panes. An edge seal is applied around each cavity to form a hermetic seal, minimising the ingress of the moisture into the cavity. A desiccant is incorporated in the spacer bar to dry up any residual moisture. Insulating glass units are assessed in their effectiveness at resisting moisture penetration by BS 5713. The air in the cavity can be replaced by another gas to give the unit specific thermal insulation or sound insulation properties. An insulating unit does NOT normally have any fire resistance properties unless it incorporates at least one pane of fire resistant glass and is glazed into an appropriate fire tested system. See also Product Data Sheet Pilkington Insulight™.

Insulation:
depending on the context, this may mean either:

  • the material applied to the back of spandrel panels to increase the thermal insulation of the panels, or
  • an alternative word for thermal insulation, or
  • the length of time that a construction can give fire resistance in relation to the passage of heat, as defined in BS 476: Part 20.

Insulight ™:
Pilkington Insulight™ is the brand name for high quality, high performance, dual sealed, insulating glass units, which are only produced by Pilkington. See Product Data Sheet Pilkington Insulight™.

Integrity:
depending on the context, this may mean:

  • the ability of the glass to hold together after fracture, or
  • the length of time that a construction can give fire resistance in relation to the passage of flames and smoke as defined in BS 476: Part 20.

Integrity only glass:
another term for non-insulating glass, see also fire resistance and integrity.

Interlayer:
the material used to separate and bond the plies of glass in laminated glass. The interlayer can be polyvinylbutyral, cast-in-place or intumescent.

Internal applications:
applications where the glass or glazing products are not exposed to natural weather.

Interstitial condensation:
literally means condensation occurring in narrow gaps, cracks or crevices. It is usually found where condensation occurs inside porous structures such as walls.

Intumescent:
capable of expanding. In terms of glass and glazing, intumescent means specifically that the material expands with heat.

This term is applied to glazing materials as well as the interlayers of Pilkington Pyrostop™ and Pilkington Pyrodur™.

Intumescent interlayer:
an interlayer which intumesces in fire conditions, not only holding the laminated glass together, but also creating an effective barrier to smoke, flames and heat.

ISO range:
the part of electromagnetic radiation, which is UV light according to the ISO definition (between 280 and 380nm). See also Product Data Sheet Pilkington Anti-Fade™.