I have a large bow window in my living room that is quite a few years old. It has (12) 14×14 glass panels in it (double pane) that seem to have lost their seal. There is moisture and dust in between some of them and they are rather drafty. Since winter is coming and I don’t want to replace the rather costly window this year, I would like to at least re-glaze or caulk the exterior and interior of the panes to keep the drafts out. Is there any benefit to using glazing compound rather than a really high quality paintable caulk? I would be tempted to think that the caulking would work better. At this point any advise would be appreciated. I have electric heat and I live in northern Massachusetts so you can probably detect the urgency of sealing out the winter weather. Thanks for your help…
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If it's an older window and single strength glass, and the glazing is shot, reglaze. If the glazing is good but your issues are coming from elsewhere, caulk 1) won't hurt anything and 2) may not fix much. You can get clear caulk that goes on white and dries clear if you don't want to paint and are just filling little voids. But I wouldn't try to substitute caulk for glazing. All this understanding this is just a finger in the dike until you can replace. Sounds like you have limited options at the moment.
Speaking of glazing, what do you think of latex glazing compound vs. the traditional oil-based glazing? I used to use oil-based, switched to latex for its convenience and quick paintability, and now I'm back to oil-based. The prime-glaze-prime-paint process is much longer with oil-based because of the recommendation that we use oil-based primer and paint throughout.
latex glazing is doggy doo. So is any of the glazing that comes in caulk tubes. Hey, you asked!
Now that is a FRANK response! But seriously, have there been any experiments on the durability of the two types of compounds? I'm reminded of the skepticism many painters had toward latex paints when they were first developed, then some fairly convincing research showed that a latex topcoat can outperform an alkyd.
The metal glazing points hold the glass in, the glazing is the sealant. Caulking from tubes will shrink to varying amounts (depends on the type) while the glazing compound from a can (like DAP or something similar) will not shrink. Personally, I'd use the oil-based glazing compound. It takes a little practice to lay it in smoothly, but it's been reliable for many a year and many a window.
Have fun!
The only way I would use caulk instead of glazing is with the understanding that this is just to get it through the winter until you can replace the glass next year.
Caulking will shrink.
Your glazer might say bad words when he has to scrape and cut the caulking off, depending on what kind you use.
Excellence is its own reward!
If the window needs replacing why bother with a really high quality paintable caulking? Get one of those hair dryer shrinking films to stop the draft.
I made some basement storms with polycarbonate windows a few years ago and used silicone sealant to glaze them (DAP/Dow Corning 100% silicone, indoor/outdoor type). Regular glazing compound would not have worked: polycarbonate expands too much.
I primed the wood with two coats of oil-based primer and let it dry two weeks. I used 1/8 inch thick backer rod between the pane and the frame. Before applying the silicone I thoroughly cleaned all surfaces (except the polycarbonate) with acetone. After applying the silicone, I tooled the beads and made the usual bevel-shape on the outside
Thus far it has held up VERY WELL. The silicone did not shrink appreciably. It remains well-adhered to the wood and polycarbonate. My only complaint: it gets a little dirty-looking.
Caulk, including silicone caulk, gets a bad rap because darn few people apply it correctly in residential applications. They don't DESIGN the joint, or prepare it right, or use a backer, or clean adequately. But look how often it is used commercially! The windows in many, many high-rise buildings are held in place by caulk alone.
Incidentally, forget the cheap acrylic caulks.
Good luck!
Thank you so much for all of your input. It is greatly appreciated... I think I'll try the old fashioned glazing method for this winter as suggested and plan on replacing the whole unit next year... Thanks again.
Ben
My understanding is that the glazing not only seals the joint between glass and frame but, properly applied, provides a sloped and self draining profile that keeps water from etching the glass and discourages leaks and freezing damage. I don't know but this from a glazier friend of mine. Not my area of expertise.
Thanks for the help, you guys are great, all of you.... I will be glazing this weekend... Replacing next summer.
Take care.
Ben