"defogging" multipane windows

[jmvannoy]

Has anyone tried a defogging service (e.g.

that claims to permanently repair fogged multipane windows? I'm not sure exactly how the process works (the web site makes reference to cleansing and draining the interior window space), but the thing that intrigues me is that they claim their process restores the insulation property of the glass. Plus a 20-year warranty against refogging.

Wondered if anyone has tried them.

Thanks, John

[Joseph Meehan]

Compare the cost to replacing the glass. Consider that anything that sounds too good to be true, likely is not true.

Replacing the glass is usually not all that expensive.

[jmvannoy]

Dia duit

They claim to be one third to one half the cost of replacing the glass.

In the case of the upper glass in a 2-story foyer, for example, the labor could be very expensive. I normally steer clear of anything that sounds too good to be true, but this seems to be a legit outfit with franchises all over the US and Canada (claiming to do both commercial and residential).

That's why I asked if anyone had tried them.

Thanks, John

[Jeff Wisnia]

I've cleared some fogged up thermopane windows by drilling a couple of holes in the outside pane's corners myself, but I didn't know anything about valves, I just left the holes open. I sort of turned them into "storm windows" that way.

I'm aware that those open holes are definitely not as good a solution as replacing the sealed units, because the inside glass surfaces will get dirty over time.

The "defogusa" website says they clean the inside of the windows. I wonder just how they do that, I suppose they may fill and drain a cleaning solution through those holes they drill in the glass.

I'm gonna investigate them because both panes of our patio door are starting to fog up, and while I've had several new panels made for smaller windows and installed them myself, the size of the patio door glass is a little intimidating for me to want to transport and install myself right now.

Jeff

[jmvannoy]

It looks like "defogusa" is one of many franchises of this company: