Short answer: yes, usually. Most people are told otherwise by companies that only sell whole windows, so it is worth understanding where the line actually sits.
What "just the glass" means
A window is a frame plus a glazed unit sitting inside it. In a modern double glazed window that unit is two panes of glass separated by a spacer bar, sealed at the edges, with air or argon between them. It is a manufactured component, and it can be removed and replaced without touching the frame.
In an older single glazed window, the glass is a single pane held in by putty, glazing beads or clips. Same principle. The pane comes out, a new one goes in.
Either way the frame stays in the wall. Nothing gets cut, no interior trim comes off, no exterior siding or brick gets disturbed, and there is no drywall repair afterwards. A typical sealed unit swap takes under an hour once the glass is on site.
When replacing just the glass works
- The window is foggy or hazy between the panes. This is seal failure, and it is the single most common reason we get called. The frame has nothing to do with it. Replacing the sealed unit fixes it completely.
- A pane is cracked or broken but the frame took no damage. A rock, a ball, a slammed door, thermal stress. The frame is fine, the glass is not.
- You want to upgrade the glass. Moving from clear to Low-E with argon, or adding laminated glass for noise or security, without replacing the window.
- The window is in a heritage district. Replacing glass within an existing sash usually does not change the exterior appearance the way a new window does, which matters in conservation areas across Hamilton, including Durand, Kirkendall, Dundas and Ancaster.
When it does not work
Being straight about this matters more than winning the job.
- The frame is rotted or structurally gone. Common in older wood windows where water has sat in the sill for years. Sometimes the rot is limited to the sill and can be repaired, typically $200 to $600. Sometimes the frame is finished.
- The frame is out of square or warped. If the opening has shifted, a new unit will not seal properly and you will be back in two years.
- The sash is a sealed factory assembly. Some vinyl windows, particularly cheaper builder grade units, have the glass bonded into a sash that is not designed to be reglazed. In those cases the sash gets replaced rather than the glass, if the manufacturer still makes it.
- The hardware has failed beyond repair and parts are discontinued. A window that will not open, lock or seal is not fixed by new glass. Cranks, hinges and locks are often replaceable at $150 to $300, but not always.
- You are already replacing the windows for other reasons. If the frames are original 1960s aluminum with no thermal break and you plan to redo them anyway, new glass in an old frame is money spent twice.
How to tell which situation you are in
Three checks anyone can do:
- Look at the fog. If the haze is between the panes and wiping both surfaces does nothing, that is seal failure and the frame is almost certainly fine.
- Press on the frame. Push a screwdriver or your thumbnail into the wood at the bottom corners of the sill. If it sinks in, there is rot. Vinyl and aluminum should feel solid with no flex or separation at the corners.
- Open and close it. If it operates, locks and sits flush, the frame is square. If it binds, sticks or leaves a gap when closed, something has moved.
If all three check out, glass replacement is your answer.
What it costs either way
| Option | Cost |
|---|---|
| Single pane glass replacement | $150 to $350 |
| Sealed unit replacement | $350 to $650, more for large or tempered |
| Patio or sliding door glass | $450 to $900 |
| Full window replacement, frame included | $600 to $1,800 per window installed |
For a house with six fogged windows, that is roughly $2,100 to $3,900 for glass against $3,600 to $10,800 for new windows. The glass route also takes an hour per window instead of a day of installers in your house.
Will new glass be as efficient as a new window?
For the glass itself, yes. A new Low-E argon filled sealed unit meets the same specification whether it goes into a new frame or your existing one. What you do not get is any improvement in the frame's own insulation or in the air sealing around it. If your frames are decent vinyl or wood, that gap is small. If they are 1960s aluminum with no thermal break, the frame will still be the weak point.
Caulking around the frame is a cheap way to close part of that gap, $75 to $150 per window.
Getting it checked
Measure the visible glass and note whether it is single or double pane, then call. We will tell you on the phone whether it sounds like a glass job or a frame job, and give you a range before anyone comes out. We do not sell full window replacement, so if we say the frame is fine, there is no second quote waiting.