Some of the most commonly asked questions I get are about how to glaze windows. What’s the best practices? What tips and tricks have I learned over the years? Basically, it’s a lot of folks wondering how to do it the right way.
I’ll start with saying this…it’s not complicated to glaze a window, but it’s not easy the first time. It is something that most people have never heard of. Putting putty on a window and tooling it with a putty knife? What?!
A lot of folks think you have to use caulk like I did before I knew better.
Caulk is not the answer by the way. You don’t need much to glaze your window properly other than a little instruction and some practice.
For a complete step-by-step guide to restoring your old windows check out my bestselling window book Old Windows Made Easy.
How To Glaze Windows
The video below will show you the mechanics of the process and help you get a feel for how a professional glazes windows. The person in this video has glazed hundreds if not thousands of windows, so don’t feel bad if you’re not up to her speed and skill, just learn from her technique.
Here’s a couple tips that aren’t in the video:
- Keep your finished putty line about 1/16″ behind the interior sight lines. When you’re done, turn the sash around and look from the inside. If you can see any putty, then you have too much putty and need to glaze a tighter line.
- Use a good quality putty (preferably a linseed oil putty) Check out my post Which Glazing Putty is Right For You? to find your perfect putty.
- Bed the glass in a thin line of putty and secure it with glazing points. The rule of thumb for installing glazing points is to use one on each side and add an additional glazing point for ever 12″ of glass size. Visit my old video How To: Reglaze Your Old Windows for the whole process from bedding to glazing. The new video is a lot easier to see the technique for finish glazing.
Enough lead in. Enjoy the 5-minute video below and keep working on those old house. They are always worth restoring!
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I love old houses, working with my hands, and teaching others the excitment of doing it yourself! Everything is teachable if you only give it the chance.
17 thoughts on “How To: Glaze Windows”
I bought type m putty and had a pretty easy time except I could never get it to form a snake.. I wore nitrile gloves and it stuck terribly. The window is sitting in my garage and it not hardened but has skinned over. I did not see the “chalking over” part until now. Will it be ok without that? Also it didn’t come out perfectly smooth. Should I have tried to mix the big container of type m putty before using? It looked oily!
The whiting isn’t necessary but only helpful for cleaning. If it’s oily then mixing the whole batch together helps a lot plus you can add some whiting to soak up the oil. Try adding more pressure with your putty knife if it’s not coming out as smooth as you’d like.
I reglazed with Type M, and I found quite hard to get the glaze smooth. First the glaze is quite sticky on hands, not so much on the wood. But more importantly, and contrary to the video, when I draw a line with the glaze to remove the excess, I don’t get a smooth glazed but a “jagged” glaze – see pic for clarity:
Any idea why is this and how to remediate?
I’ve scoured the internet and various fora and cannot find an answer to this question: When you’re re-glazing the lower sash, and the meeting rail has a groove where the glass slides in, I get that you fill the groove with glazing compound to bed the glass, but do you still glaze that side? If you do, you will see it from the interior of the window, as there is no wood trim to hide it on that side. But I’ve never seen anyone explicitly say you only glaze three sides of a lower sash. We’ve done two out of 12 windows, glazing all four sides. The glazing is terribly visible from the interior just below the meeting rail. But we’re afraid to not glaze that top side if somehow that’s bad for weathering. Please help!
My windows have that channel. There is bedding glazing in the channel but there is no external slanted glazing on that side. So yes, only 3 sides have the external glazing.
Bed the glass in a thin line of putty and secure it with glazing points. The rule of thumb for installing glazing points is to use one on each side and add an additional glazing point for ever 12″ of glass size. Visit my old video How to retrofit glazing your Old Windows for the whole process from bedding to glazing. The new video is a lot easier to see the technique for finish glazing.
Wrap-up. I let the Sarco sit for about 10 days, then gave it 2 coats of oil-based paint, no primer. It took the paint perfectly. Success!
OK, I reglazed today. Wow, the Sarco is SO much better than the DAP. Way easier to get a crisp line. Corners went very well – they were a lost cause with the DAP. At first, I was a little concerned that it didn’t seem to stick to the sash well, but that didn’t prove to be an issue. Not impressed with the Fletcher point setting tool – it wouldn’t push the 3/8 diamonds in far enough, so I had to finish with a screwdriver. The Mintcraft glazing putty knife works well for me. Nice and stiff, and the angled handle is just right.
Glad to hear it went well! The point tool works best with the larger points and triangles or you can grind it down just a bit like I did and now it’s perfect for the 3/8″ points.
Just got my Type M from you. The DAP is in the trash can. It’s summer in Memphis, and the temps in my garage are pretty hot. We’ve got a couple of nice cool mornings, so I’m going to reglaze, then I think I’ll let it sit inside the house for a couple of weeks to skin before painting it.
Awesome Buddy! Type M should be ready if it’s in the garage in about a week. Keeping a fan on it also helps it skin faster. Good luck!
I reglazed a window, let the putty sit for a week in 85 degree temps, then primed with oil based Kilz. A week later, the primer is still tacky. What happened? Do I need to start over from scratch?
It depends which putty you used if that was too soon. 1 week should be good for Sarco Type-M but not for DAP 33 or Sarco Dual Glaze. Also, you should not prime the putty. Only top coat with paint.
I used Dap 33. How long does it need? Do I need to scrape it out and start over? Or just paint over the tacky primer? Or something else?
I would dig out the dap and start over. Try some Sarco Type M from my website if you can paint it in just a few days. Or you can use Sarco Dual Glaze if you need more time before painting. Always skip the priming of the putty.