Thermal windows are manufactured to be a sealed unit.  But it is difficult to maintain a perfect seal.  Manufacturing, transportation and installation can destroy the seal.  The atmospheric pressure changes exposure to weather and the radiation from the sun all act on that seal.

 

The majority of failed thermal glass units are found on the sunny side of the property because of the extreme heat exerted on the windows.  In a test I did I built a thermal pane inside a wood frame and put a thermometer inside.  The temperature reached 140 degrees before breaking the thermometer and the black casing warped.

 

When it is very cold the pressure inside a window drops.  The window can even suck water into it.  This especially happens in high humidity areas like bathrooms.  On one bathroom window I worked on the window had filled up 2 inches with water and when I drilled into the space bar the window continued to pull air into the window until the pressure had equalized to outside air pressure.

 

Eventually because of this all windows will fail.  Average lifetime is

12 years. 

 

[The Readers Digest magazine The Family Handyman talks about this cycle that causes windows to fail]

 

Thermal glass units are manufactured with desiccant or moisture absorbing material to help the window deal with this process.  After the desiccant is saturated the window will start to fog up.  In early stages the fog will come and go with temperature and humidity changes.  As moisture becomes permanent the combination of heat and water will start to leave deposits and then etch the glass.   Once the glass is etched we may not be able to restore the unit.

 

 

How we cure a Window

 

Our process re-engineers the window to reverse the accumulation of moisture.  We drill small vents into the window, either directly through the glass or into the spacer bar of the window.  Now as the window heats up and the air expands it starts to release the moisture out of the window.  Imagine a partially full water bottle with it’s lid tight in the sun.  The water will never dry out because the water has no where to go.  However remove the lid, and put an attachment over the lid to make sure no rain, snow etc can get inside.  It will dry out and stay dry.  We are basically doing the same thing with a window.  The key is (1) make sure the moisture has a place to go and (2) make sure water cannot get back into the window, either through the vent we drill or though the seal.

 

Another positive aspect of this process is that the vents, fitted with the valve or sieve over them act to pressure regulate the window.  No longer will the heat put external pressure on the seals or will the extreme cold cause the window to be at a negative pressure and pull moisture into it.

 

The benefits of this process:  No mess from tearing apart the window sash or frames to replace the window or thermal glass unit.  Reduce green house gas emissions by reducing the manufacturing and transportation of glass and other window components.  And waste glass to fill landfills.   And the cost is significantly less that replacing the glass or the window.

 

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