Montreal foggy sealed unit repair — save the frame

Fog, haze or a milky film trapped between the panes means the sealed glass unit has failed and its argon has leaked out. We replace just that blown double-pane unit and keep your frame and sash — matched glass, Low-E coating and the right spacer, sealed and warranted in writing.

Every opening measured on-site

Full air-seal on every unit

Written frame + sealed-glass warranty

Fog means the seal failed, not the window

When you see haze, condensation or a milky film trapped between the panes that will not wipe away, the sealed glass unit has failed — the edge seal let go, the insulating argon escaped, and humid air fogs the glass from the inside. That pane has lost most of its insulating value, but the frame and sash are almost always still sound.

So a fogged window is usually a glass problem, not a whole-window problem. We swap in a new sealed unit sized and glazed to match, which restores the clear view and the efficiency without the cost of a full replacement.

If the pane is cracked rather than clouded, see window glass repair; if you would rather upgrade the whole opening, we also handle double-pane upgrades and energy-efficient replacement across the region.

Four steps to a clear, sealed unit

Book the estimate

Call, text or use the form. We book a free in-home visit — no obligation, no high-pressure sales table.

On-site measure

We measure every opening, check the frames and sills for rot or water damage, and walk through material, style and glass options in plain language.

Written quote

Line-item quote with the window line, glass package, U-factor, warranty and haul-away on one page. Financing attached when you want it.

Install, cleanly

Drop cloths, boot covers and a full air-seal on every unit. Old windows hauled away and a walkthrough of your new windows plus warranty registration.

Save the window, lose the fog

Replacing just the sealed glass unit costs far less than a whole new window and brings back both the clarity and the insulation the blown unit lost — one of the most cost-effective repairs we do in Montreal winters.

We measure the unit, then match the glass and glazing — double- or triple-pane, Low-E, the right warm-edge spacer — to your other windows so the repaired one looks and performs like its neighbours, sealed in tight and backed in writing. Explore all our window repair services, compare a full window replacement, or book a free estimate to get started.

Montreal foggy sealed unit repair, answered

Why glass fogs, cost and whether every unit can be fixed.

Why is my window foggy between the panes?

The sealed unit — the two or three panes bonded around a spacer to trap insulating gas — lost its seal, usually from age, heat cycling or a manufacturing flaw. Once the seal fails, the argon escapes and humid air seeps in, and when that air cools it condenses into the fog you see between the panes. It cannot be cleaned or dried out, because the moisture is sealed inside the glass unit; the unit itself has to be replaced. The frame around it is typically fine, which is why this is a repair, not a replacement.

Do you replace the whole window?

Usually not. In most cases we replace just the sealed glass unit and keep your existing frame and sash, which costs a fraction of a whole new window and solves the problem completely. The frame is rarely the issue when a window fogs — it is the glass unit that failed. We only recommend a full replacement if the frame or sash is also rotted, drafty or damaged, in which case we will show you the numbers both ways. For a simple fogged pane in a sound frame, a unit swap is the smart fix.

Can every foggy window be fixed this way?

Most can. If the frame and sash are sound — which they usually are — we can replace the fogged sealed unit and keep the rest of the window, whatever the style. The exceptions are windows where the frame or sash is also failing, or a few older or specialty units where a matching sealed unit is hard to source; in those cases we will tell you honestly and lay out the options, including a full replacement if it makes more sense. We check the whole window at the measure, not just the glass, before we quote.

How long does a sealed-unit replacement take?

We measure first, order the matching glass unit, then swap it in once it arrives — usually a quick single visit for a standard size.

Will the new glass match my other windows?

Yes — we match the glass type, coating and spacer so the repaired unit looks and performs like its neighbours.

Book a free Montreal foggy sealed unit repair estimate

Foggy window? Book a free measure and a written quote for sealed-unit repair anywhere across Montreal and the surrounding towns — a new glass unit matched to your window that clears the fog and restores the insulation, for a fraction of a full replacement. Done by our own crews, no subcontractors, no pressure.

Locally owned · Insured · ENERGY STAR® · Free written estimates

Real Montreal reviews

What Montreal homeowners say after the fog cleared

★★★★★ 4.9 · 118 reviews on Google

★★★★★

Three windows had gone cloudy between the panes. They swapped just the sealed units and kept our frames — saved us a fortune.

C. Bergeron

Homeowner, Montreal

Explained the seal had failed and we did not need whole new windows. Clear glass and insulation back in one visit.

S. Aujla

Homeowner, Laval

Honest repair over a needless replacement. Matched the glass perfectly and the fog is gone.

J. Fortin

Homeowner, Longueuil

Fast, fairly priced and no upsell. The view is crisp again and the room warmer.

P. Nkemelu

Homeowner, Gatineau

Montreal foggy sealed unit repair — save the frame

Fog means the seal failed, not the window

Four steps to a clear, sealed unit

Book the estimate

On-site measure

Written quote

Install, cleanly

Save the window, lose the fog

More Montreal window repair services

Glass Repair

Screen Repair

Hardware Repair

Sash Repair

Montreal foggy sealed unit repair, answered

What Montreal homeowners say after the fog cleared

Montreal window guides

How to Choose the Right Windows for Your Montreal Home

Book a free Montreal foggy sealed unit repair estimate