Foggy Window Glass Replacement — New Sealed Unit, Same Frame
Haze or water between the panes means the seal has failed. If the frame is still good, only the glass needs to go.
JMB Builders does foggy window glass replacement across the Twin Cities metro. When the seal between the panes fails and the glass fogs, we measure the sealed glass unit, have a new one made to size, remove the glazing stops, take out the fogged unit, set the new one on setting blocks, and reseal it in your existing sash or frame. Priced per window, quoted from photos.
- Priced per window, glass supplied
- Keeps your existing frame and trim
- Quote from photos, measure before ordering
- Licensed MN contractor BC809005
A double- or triple-pane window is a sealed glass unit set into a sash or frame. When the edge seal fails, moist air gets between the panes and condenses there. You cannot wipe it off because it is inside. Over time it leaves a white film that stays even when the fog clears.
If the frame and sash are sound, you do not need a new window. The sealed unit is measured, a new one is made to the same size and thickness, and it is set back into the existing sash or frame with new glazing tape or sealant. It is the right fix for a picture window or a large fixed pane in a good frame. On an old or rotted window, or one where several sashes have failed, a new window is usually the better use of money, and we tell you when that is the case.
What you supply
- Photos of the fogged glass and the frame around it
- Any label or stamp on the glass spacer (it often shows the brand and date)
- Your window's warranty paperwork if you have it — seal failure is often covered
What JMB supplies
- Measurement of the sealed unit before it is ordered
- The new sealed glass unit, made to size and thickness
- Removal of glazing stops and the fogged unit
- Setting blocks, glazing tape or sealant, and reinstalled or new stops
- Haul-away of the old glass
- Photos of the finished window in your job folder
How it is priced: per window
Quoted in writing from your photos within one business day. What moves the number:
- Size of the glass and whether it is double or triple pane
- Tempered, laminated or Low-E glass required
- Fixed pane vs. a sash that has to be removed to reglaze
- Glazing stops that come out clean vs. ones that break and need replacing
- Access: ground floor vs. second story
- How many units in the same visit
Send a photo of the fogged glass, the corner of the frame, and the stamp on the spacer bar if you can see one.
How long it takes
Two visits: one to measure, one to install once the glass arrives. Install is usually an hour or two per window.
How your project works
- 1
Photos and a quote
Send photos of the fogged glass and the frame. We tell you whether glass-only makes sense and give a written quote within one business day.
- 2
Measure the glass
We measure the sealed unit's size and thickness and note the glass type, including tempered or Low-E where needed.
- 3
New unit made
The replacement sealed unit is made to those measurements. Lead time is written on the quote.
- 4
Reglaze
Stops out, fogged unit out, new unit set on setting blocks with glazing tape or sealant, stops back in, glass cleaned.
Situations and options
Fixed picture window glass
The most common glass-only job. The frame is sound and the pane is large, so replacing just the sealed unit saves the frame and trim.
Operating sash reglazed
The sash comes out of a double hung or casement, the unit is replaced, and the sash goes back in. Works when the sash itself is in good shape.
When a new window is better
Several failed units, rotted sash wood, or an old aluminum frame. A new window costs more once but fixes the frame too; we price both when it is close.
Foggy Window Glass Replacement — New Sealed Unit, Same Frame: questions, answered
Can you replace just the glass in a foggy window?
Yes, if the frame and sash are sound. The sealed glass unit is measured, a new one is made to size, and it is set into your existing frame. You keep the frame, the trim and the rest of the window.
What causes fog between window panes?
The seal around the edge of the glass unit has failed. Moist air gets between the panes and condenses as the temperature changes. It cannot be cleaned from the inside or the outside.
Is glass replacement cheaper than a new window?
Usually, for one or two panes in a good frame. If many sashes have failed or the frame is rotted or leaking, a new window is often the better money. We price both when it is close.
Is foggy window glass covered by warranty?
Many window warranties cover seal failure for a period of time. Check your paperwork or the stamp on the spacer bar between the panes, which often shows the maker and date. Call the manufacturer before paying for glass.
Can you defog a window instead of replacing the glass?
Some services drill and vent the unit to clear it, but the seal is still broken and the gas fill is gone. It looks better; it does not insulate like a sealed unit. Replacing the unit restores the seal.
How long does foggy glass replacement take?
It takes two visits: one to measure, one to install once the new unit is made. The install is usually an hour or two per window.
Recent JMB work, from our job log
59 installs recorded across 30 Twin Cities communities since Dec 2025. Window and door installs for homeowners and for the builders and dealers we sub for. Counts come straight from our job log; no customer names.
Get a written quote for this job
Three photos and a sentence is enough. You hear back within one business day. Or text the photos to 763-204-2099.
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Read morePage reviewed September 26, 2026 · JMB Builders LLC, MN license BC809005 · All windows pages
Where we work
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Based in Zimmerman, scheduling across the Twin Cities metro. Closest first: