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FAQ's - This page will have items added and intends to be informative and address the most questions customers ask. While it doesn't cover every aspect of the window business it cover the questions customers ask every day. We may accept suggestions for additions should you send us a request via email about interesting topics in the industry.


Why does double insulate glass "fog"?  

That's probable the most frequent question in this industry. Double insulated glass also known as IG, has 2 panes of glass separated by a metal (or other materials) spacer with a rubber like seal around it.  After many years of contraction (winter) and expansion (summer), the seal will eventually get separated from glass and through that gap air is sucked into the unit. The air naturally contains moisture which will form that condensation most of time. Sometimes the water will leave whitish marks on glass which are nothing more than the minerals from water such as calcium and silica, etching the glass permanently. The glass will lose part of it's insulation efficiency and become cosmetically unattractive. 




Is it necessary to replace the whole window when the glass is fogging?

No. The glass can be replaced without replacing the entire window. It's much more cost effective, faster and you don't have to worry about matching the adjacent windows. Also, if the window has 2 independent sections and just 1 is fogging that can be replaced independently thus saving you money.



How about "defogging" without replacing the glass?

Some companies claim they will fix you glass without replacing it. They drill a hole in the glass insert a nozzle in it and squirt a cleaning solution to clean those mineral deposits and then install a valve in the hole which will make the glass "breath". While it might work occasionally we don't believe it's effective or permanent. First, the white stains inside the glass cannot be completely cleaned because the glass has been etched permanently when it gets visible. Second, the valve they install will not be the only opening allowing air in and out. The seal is already compromised and won't be restored. Furthermore, if the glass is tempered, it will shatter when drilling is attempted (safety glass cannot be cut or drilled). "Defogging" is a popular practice in Canada which is another reason it might work sometimes in an environment with much milder summers. In short, it doesn't work all the time and will be effective as far as getting cleaned if done at the very beginning when the glass lost the seal which is a very hard to detect because evidence is not visible at this early stage.


Can I replace just one side of glass if it's broken of foggy to make it cheaper?

In fact it's not cheaper to replace just one side of double insulated glass because it's time consuming, labor intensive and much more difficult than replacing the whole unit. Even if the installer manages to separate the glass without breaking it, the minerals cannot be cleaned effectively and the seal won't be restored because there no easy access to it when already sitting on the window frame. That would be a patch without any warranty and it could fog again in a very short period of time. 






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