These summarize my points on window replacement versus IG Glass Pak replacement:
• I don't recommend the IG option as the cost savings is not significant compared to replacement windows. I have included some comments from various websites. The assumption favoring the glazing option is based on a $500-$800 glazing option (see below) versus $1,000-$1,400 for full replacement. The incremental labor is more as you are replacing two units of glass on a single/double hung versus one unit with a replacement window. This is what pushes up the cost of the IG option. My quote for a full replacement window is at the $550 range with bronze exterior and white interior, so well below the estimated price used in the comparison.
• The glazing bead on the existing frame could be damaged without obvious signs which could lead to seal failure at some future time, clouding the new glass pak and thus still have a defective window unit.
• Replacing window glass in old aluminum frames requires a more difficult and expensive process that one in a wood window as the previously mentioned glazing bead has to be matched up and set correctly.
• As mentioned in the post below, aluminum windows like yours (20 plus years of age), should be replaced versus re-glazing the window glass as replacement provides a much more energy efficient option.
• The IG units are not warrantied past thirty days.
• Additionally, the frames are still old and will leak energy and will still allow wind, dust and noise around the frame.
• There also could be undetected wood rot with an IG only replacement. While that would be an extra charge with a window replacement, at least the homeowner would know.
LCD’s response on Angie’s List 5/14:
The fogged window "repairs" will refog in short order, yes, because they just flush out the moisture (commonly leaking water stains on inside of glass) and seal the holes used to do that - does NOT repair the original leak at all, so waste of money and a scam, in my opinion.
However, complete "glazing unit replacement", all the glass and intermediate film layers plus the metal frame it is mounted in complete with seal and inert gas, replaced in the existing frame, will typically cost 1/3-1/2 as much as complete window unit replacement, which is also called "full unit replacement" or "prime replacement" in different parts of the country. Usually replaced at your house - they come once to measure each unit, then come back with factory manufactured glazing units to install and caulk in place. Will likely need some touchup painting afterwards, which window replacement places usually do NOT do - you will need a handyman or painter for that.
A third option, costing typically 2/3 as much as a total new unit, is "construction window replacement" or "slider replacement" - replacing the moving parts of windows or the inner frames including the contained glass, but not the outer frame they sit in, assuming the outer frames are not rotted or out of square. Cannot be done with all types windows, and if not a highly professional firm can result in sticking or drafty or leaking windows. These would then interior and exterior painting/staining to match.
If windows are 20 years old and you have many windows to do, you would normally replace them for newer more energy efficient and lower maintenance materials, but if out of the budget then glazing unit replacement can be a viable alternative. One other thing with replacing glazing units - little savings in doing a lot over one or a few at a time, so you can fix only the really bad ones initially then other a year or few down the road, without having a difference in appearance from the outside or inside, like if you did a prime replacement on only some units.
Glazing replacement depends on how many panes you have and type of intermediate triple-pane film if any, inert gas or not and type, special coatings, etc - but glazing unit replacement for a 4x6 window probably around $500-800 installed versus $1000-1400 range for full unit replacement, typical range. Smaller windows are cheaper, comparatively, because more of the money is in the frame and less in the glass.
Houselogic comment (Undated)
• Symptoms: Cracks, scratches, or chips.
• Cause: Johnny’s home run, storm damage, abrasive cleaners.
• Cost to repair: Replacement glass, $3-$14/sq. ft.; hiring a handyman to install glass, $100-$300; replacing sash (the frame that holds the glass), $40-$250 (vinyl).
• Repair or replace? Replace inexpensive vinyl windows. Repair vintage, aluminum-clad, and multi-pane custom windows that could cost upwards of $500 each to replace.