How did the glass fall? A temperature or stress crack will not leave the sash normally.

It just dropped i guess - i didnt see it happen - i heard the noise and when i went to investigate i saw glass on the floor. Some is still in the sash

I will try to attach photo

Inside or outside pane of glass?

Inside

Is it above a kitchen sink?

No - it was windows in 2 rooms - 1 was a rarely used powder room and the other was in the main hallway. i just moved the broken glass to the counter next to the garbage.

Anything is possible, but even if they had a longer warranty for stress cracks (a one year warranty is not uncommon), you may get that declined anyway. A stress crack typically shoots out from an imperfection on the edge of the glass and is just that, a single crack--at least to start. The other factor is that stress cracks will typically occur within the first year or two in extremely hot or cold temperatures. Seven years combined with completely broken glass really doesn't fit the mold. Again, not saying that its impossible, but I know that there are manufacturers that would turn that claim down even if within the warranty period.

I love it when Obie 1 breaks down glass breakage. Be prepared for an answer in 500 words or more.

lol! Old habits are hard to break (intentional bad pun, sorry).

thanks for your response! they broke abour an hour apart - 7pm / 8 pm. we had a huge temp drop that day down to real feel in the negatives. the windows are next to each other facing the front on the house (but are 2 different rooms inside). if i recall correctly they came finished on the exterior but we had a painter paint the inside. Do i need to worry about all of my windows breaking? i cant believe how mucn it is to replace - not including the labor.

Would it be possible to get a close up picture of the areas that I circled in the pictures above? I have an idea what caused the breakage but I don't want to speculate without a close up look at the possible break points.

I can make an educated guess about other windows once I see that.

Thanks

Uh oh. Hound-dog is on the scent.

LOL!! Yeah, hoping I can help.

is this what you need? the other broken window is covered better so it would be harder to get to, let me know if you need that one also.

@mmrce6 thank you. What I was really trying to see was a close up of the possible break origination. Really difficult with condensation on the glass and such, but no worries and here is what I am thinking.

Two things I was looking for, first was a horizontal crack from the muntin bar, which might be there in this close up, and to look at the vertical crack close to the muntin bar to see how parallel it is to the bar.

One other question I forgot to ask, do you have a bar between the glass covered by the muntin bar?

Two things from your pictures: first, your windows broke under some serious stress, and second is that the break appeared to originate at the muntin bar (both windows) and not at the outer edge of the IG unit which would be much more common. That the break appeared to be from the edge of the muntin bar my immediate thought was that your windows were painted on site and not from the factory and that's why I asked about painting in my first reply.

Thermal stress breakage is almost always related to uneven heating/cooling of the glass rather than an overall high or low temperature. Thermal stress breakage is also usually very easy to identify and even quantify based on the location of the breakage and the characteristics of where the break originated and how it grew from the origination point.

Without going into all the details, uneven temperature in the glass adds stress to the glass, and given enough stress the glass will crack. The greater the stress the more cracks will appear in the glass. Your breakage appears to have some characteristics of thermal failure and that's why I asked for close ups, but just because glass is hot or cold isn't a reason for it to break. Glass breaks due to stresses in the material and just being hot or being cold, especially within the very narrow limits of what we consider hot or cold at the temperatures we need to survive, there needs to be contributing factors.

I suspect (and I am speculating based on pictures and descriptions, so keeping that in mind) that your painter used a razor blade to clean up along the edges of the glass, something very common (I have done it too), but something that can introduce flaws in the glass, even at microscopic levels. Normally glass can easily handle stress introduced by temperature swings, even severe ones, but because of possible flaws introduced into the glass due to being scored by the razor blade the stress was too much and the glass broke.

Again keep in mind that I am speculating based on what evidence is available using pictures and descriptions, but that's what I am seeing.

Is there anything unique about these two windows compared with others in your home? Do they face west by chance? Do they get full sun or are they usually shaded?

Ugh - im the orginal poster and i cant believe it, another window just cracked! its above freezing outside. Why does this keep happening? im going to have to replace all my windows. its dangerous to have glass shards falling out of my windows. Is there anyone that can inspect the remaining windows?

My original reply still stands, I believe that the glass was damaged when the windows were painted, but I would be a lot more certain that's the cause if it was summer.

Do the windows that have broken all face the same direction? If so then west?

Do you have pictures of the latest one??

Call Marvin directly and tell them what's happening. Tell them that you aren't calling about warranty, tell them that you are calling because you are worried about your family's safety because your window glass is breaking without warning and you don't know why. Not just cracking but breaking and glass is falling on the floor.

Don't stop with customer service if they aren't helpful, ask to talk with a supervisor if they say they can't help you.

" did your windows come painted from the factory or were they painted on site??? "

Was this ever answered? If interior was field painted do you know the paint type? Possible the grille bars stuck to the glass and eventually expansion and contraction broke the glass? The breaks look like they are concentrated toward the vertical grille bar.

Hi - thanks so much for responding! i spoke with someone different at Marvin today (this time in the warranty dept, last time it was customer service). He said yes this was becoming more of a common problem, though still not very common, and is under warranty and he’ll take care of it. I believe the paint was Benjamin Moore. The rep today gave me off the record tips about some problems I could look for or ways to relieve pressure if i was concerned about it happening again. A much more helpful conversation this time around with Marvin.

Well that is good news !! I thought it was pretty bad that they said the windows only had a one year warranty. Somehow I was under the impression that most windows had a ” lifetime” warranty (but who knows how many years that actually is…)

Very glad to hear that Marvin is going to work with you on this, and I am really curious what exactly they said about what happened. Also very curious about what the rep suggested for relieving pressure, and what pressure he was referring to. Are they suggesting replacing all sashes or only those that have broken?

The breaks definitely occurred from the edge of the muntin bar and almost certainly were related to painting, but if I was doing an analysis of the cause the first thing I would look for would be a score line along the edge of the muntin bar due to cleaning the edge with a razor blade. Unfortunately that is a real thing that I have seen a number of times in the past (including a few Marvins).

And as an aside, never assume that window company folks know much of anything about glass, other than they put it in their frames and you can look through it.

I thought it was pretty bad that they said the windows only had a one year warranty. Somehow I was under the impression that most windows had a ” lifetime” warranty (but who knows how many years that actually is…)

Marvin has 20 years on glass and I believe 10 years on frame/sash/etc.