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Replacement Window Insulated Glass Unit

Replacement window education

An insulated glass unit (IGU) is made with two panes of glass and to keep the two panes separate a low conductive spacer is used to make the unit efficient and keep the two panes of glass sealed.  

All high quality replacement windows have some type of spacer system to keep the unit sealed and prevent conduction within the overall IGU.  Much like the panes of glass that make up the unit, the spacers are typically cut precisely by a laser reading from a computer that instructs the cutting machine exactly what size to make the spacer component of the window.

Another important function of the spacer is to have notches put in if the window is to be assembled with a grid pattern.  The notches actually hold the grids in place so they do not move over time or during shipment.

Sealing the IGU

Before the final step in the sealing process of an IGU is to

In order to improve the insulating quality of the overall glass unit,  butyl is added to the edges of the IGU.  Butyl is esentially rubber.  By adding butyl to the edges it increases the thermal barrier and ensures that replacement window will perform as it is designed to do.

The final step once the rubber seal is injected into the edges of the glass unit, the entire portion of the window is placed in an oven to seal. As it leaves the oven after a precise amount of time, the IGU is then compressed at precisely the right temperature evenly acroos the unit to complete the seal.

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