My home is 4 yrs old, with low e glass with metal coating (not film). Several sashes have developed a spotting, metallic-looking discoloration on the interior of the glass. I'm being told it is due to the builders cleaning method of the concrete siding. True? How impervious should the glass seal be to the acid wash? Can it be "fixed", short of changing the windows?
Reply to [B]Jurgen[/B]:
> I suppose you have a double glazed unit. In this case low-e coating is usually located inside double glazed unit. If this is the case, there is no way that double glazed units can be clean on the inside. Also secondary and primary edge seal should hermetically assemble the whole unit in order to prevent different intrusions. I find it hard to believe that the polishing agent has entered the inside of double glazed unit. If this were the case you would also experience moister inside double glazed unit.
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> Is it possible that the discoloration was present when you bought the window?
Yes, the units are double-glazed. The discoloration was not apparent until this past year (4 years old), and it is between the panes. I'm told it is a reaction of the muriatic acid wash, used on the concrete as a standard builder practice, with the low e metallic coating. The muriatic acid wash was able to get inside the sash, as the seal used between the panes is not impervious to the acid wash. My questions are: is this valid (seal susceptability to the wash)?; discoloration (due to acid contact with low e coating)?; and, can the sash be tested to determine the if this is the failure mode?
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I am not exactly a double glazed specialist. I am aware that low-e coating reacts to some acid causing stains. However I am still not convinced that low-e selling can allow acid was to get inside unless the window has broken down. However while navigating through the web I found a forum dedicated to double-glazing problems. I am sure you will be able to find a right answer there http://www.thewindowman.co.uk/chatweb/index.htm
I suppose you have a double glazed unit. In this case low-e coating is usually located inside double glazed unit. If this is the case, there is no way that double glazed units can be clean on the inside. Also secondary and primary edge seal should hermetically assemble the whole unit in order to prevent different intrusions. I find it hard to believe that the polishing agent has entered the inside of double glazed unit. If this were the case you would also experience moister inside double glazed unit.
Is it possible that the discoloration was present when you bought the window?