Replace the unit
The frame is square, the sash opens and locks, and there is no rot or corrosion. Only the glass has failed. This is the common case and it is a fraction of a new window.
Cloudy, fogged and failed sealed units
Foggy double pane glass replacement
If the haze is between the two panes, the seal on the glass unit has failed. The fix is a new insulated glass unit set into the frame you already have. The window itself almost never needs to come out.
Serving the Wasatch Front, Park City and Tooele.
- Licensed and insured
- Frame, trim and siding stay put
- One year warranty
- Free written estimates
Request a sealed unit estimate
Tell us how many windows are fogged and roughly how big they are.
Got it. We will call you back.
Your request is in. If it is urgent, call (801) 678-5770 and we will pick up.
Why a double pane window goes cloudy
A double pane window is not two loose sheets of glass. It is a sealed unit: two panes held apart by a spacer bar around the edge, with a sealant bonding the whole edge shut and a desiccant inside the spacer to soak up the little moisture that was sealed in at the factory.
That edge seal is working every day. The air in the cavity expands on a hot afternoon and contracts overnight, and on the Wasatch Front the swing between a summer day and a winter night is large. Over years the seal fatigues, humid air gets in, the desiccant fills up, and the moisture starts condensing on the inside faces of the glass.
At first it comes and goes with the weather. Later it leaves a permanent white film, because minerals in the condensed water dry onto the glass and etch it. By then no cleaning of any kind will clear it, from either side.
The frame is usually fine. What failed is the unit, and the unit is the part we replace.
Haze on the room sideOrdinary indoor condensation. The unit is working. Ventilation, not glass.
Haze on the outside faceNormal on cool mornings with an efficient unit. Nothing is wrong.
Haze between the panesThe edge seal has failed. The unit needs replacing.
How a sealed unit gets replaced
Two visits, because the new unit is built to your measurements rather than taken off a shelf.
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1
Measure and check the frame
We measure the glass itself, not the window, and note the unit thickness, the spacer, and whether it is tempered or has a coating. We also check the sash and frame, because a new unit in a rotted or bowed frame is money spent twice.
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2
The new unit is fabricated
Insulated units are made to order to the exact size and build of the old one. Safety glass is ordered wherever the location calls for it, which the code decides, not us.
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3
Swap it in the existing frame
The stops or glazing beads come off, the old unit comes out, the new one is set on setting blocks and sealed, and the stops go back. Your trim, siding and paint are not touched.
Glass unit or whole window: which one you need
Most fogged windows are a glass job. Some are not, and it is cheaper to hear that at the estimate than after the glass is ordered.
Replace the window
The frame is rotted, split or out of square, the sash will not seal, or several units in the same window line are failing along with the frame. We will say so, and that work belongs to a window replacement company.
Grilles inside the glass
If the grid pattern sits between the panes, it is part of the unit, so the whole unit is replaced. Tell us at the estimate.
Patio doors fog too
A slider panel is a large tempered sealed unit. See sliding glass door glass.
Cracked, not fogged
A cracked unit is replaced the same way. If it is broken out, see window glass repair.
What a new sealed unit costs
Every unit is built to size, so the real number needs the glass measured. What decides it is predictable.
Unit in a sound frameLower costThe usual outcome
The unit alone is replaced. No frame, no trim, no siding work.
Tempered or coatedHigher costWhen the location needs it
Safety glass beside doors and low to the floor, and low-E coatings, cost more to make.
Several windowsBatchedOne measure, one install
Several fogged units measured and fitted together cost less per unit than one at a time.
Foggy window questions
How do you get rid of condensation between double-pane windows?
You cannot clean it out, because it is not on a surface you can reach. Condensation between the panes means the seal on the insulated unit has failed and moisture is now inside the sealed cavity. The fix is a new insulated glass unit in the same frame. Defogging services drill and vent the unit, which clears the view but does not restore the seal or the insulating gas.
Will condensation between window panes go away on its own?
No. It may look better on a dry day and worse on a humid one, which fools people into thinking it is clearing, but a failed seal does not reseal itself. Once moisture is in the cavity the unit will keep fogging and the deposits gradually etch the inside of the glass permanently.
Can a foggy double pane window be repaired, or does it need replacing?
The glass unit is replaced, the window is not. The insulated unit comes out of the existing frame and a new one goes in, so you keep the frame, the sash and the hardware. That is a fraction of the cost of a full window replacement, and it is the right answer whenever the frame itself is still sound.
Why are my windows foggy between the panes?
Because the edge seal of the insulated glass unit has failed and humid air has gotten into the space between the two panes. The desiccant in the spacer can only absorb so much, and once it is saturated the moisture condenses on the inside faces of the glass. It is a failure of the unit, not something you did.
Does defogging a window actually work?
It clears the view, sometimes for years, but it does not restore the seal. Defogging drills small holes in the unit, dries and cleans the cavity, and plugs the holes. The seal is still broken and any insulating gas is gone. Replacing the unit restores both the clear view and the seal.
Is a foggy double pane window covered by warranty?
Often, if the window is young enough. Many window manufacturers warranty the glass seal separately from the frame. Check the manufacturer name etched in the corner of the glass or printed on the spacer and ask them first. If it is out of warranty, the unit can still be replaced on its own.
Get your fogged windows measured
Tell us how many and roughly where they are. We will measure the glass, check the frames and price it in writing before anything is ordered.
Broken rather than fogged? See window glass repair.