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Re: Condensation problem inside storm windows
hlhood wrote:

Advice on replacements for 8 over 8 and 6 over 6 paned windows would be welcome as well. --hlhood

When I first got on the internet, I was surprised people on these DIY Q&A forums didn't know that glazing putty was nothing more than clay or chaulk mixed with linseed oil, and that glazing putty cured by reacting with the oxygen in the air just like linseed oil based paints so. So, I answered a lot of questions about how best to replace glazing putty and repaint glazing putty with oil based paint, even though I don't have any glazing putty in any of my 66 windows.

But, until you have the opportunity to replace your large multi paned windows, you're stuck with maintaining them, which will normally mean replacing the glazing putty around each pane every 5 to 10 years. Your best friend if you have such windows are awnings over your windows or a wide overhang on your roof that will keep rain off the windows.

Probably the best thing you can do is realize that your multi paned windows were made before high tech caulks were available. They were made when the only window sealant was putty. But, you don't need to keep replacing putty with putty. If it were my windows, the next time I removed the old putty, I would replace that putty with Kop-R-Lastic caulk, and then paint over the caulk. Not only would that caulk hold the panes in place as well as putty (along with the glazing points) in anything short of a hurricane, but it would be a cakewalk to remove any caulking and replace it if and when necessary (like the neighbor's kid puts a baseball through one of the panes). Like I say, with this Kop-R-Lastic stuff, you just get one end started and the caulk pulls off like a rubber rope.

Just keep this post in mind so that in the future when you next have to do any maintenance on your multipane windows, you'll realize that you don't have to replace putty with putty. Replace it with something that'll last 50 years instead of 10, and be much easier to service as well.

PS: you don't need to know the rest...

Here's a picture of me pulling some Kop-R-Lastic caulk off of one of my windows:

The Kop-R-Lastic caulk in this picture has been on for about 5 years. If it's only a few months old, it wouldn't be nearly as strong and would break as you pulled it off.

You can see from the blood circulation (or lack thereof) in my fingers that the Kop-R-Lastic puts up a pretty good fight to stay on. It WILL NOT come off of it's own accord.

In my case, I had new PVC "roller windows" installed into existing wooden window frames. Roller windows are similar to sliders except that you have a triple glazed sealed unit in each of two PVC window frames, and the two PVC window frames roll past each other on PVC rails similar to bypass sliding doors. I like that design because it means the window is open or closed and nothing in between so I don't have tenants closing only one of three sliders in the winter so that the one closed slider sweats and gets all frozen closed. The window is either open or closed, and that means no frozen sliders.

The Kop-R-Lastic caulk is about the only thing holding the plastic flashing in the picture in place (beside several short pieces of double sided tape). That plastic flashing covers the caulked gap between the PVC window frame and the wood stop moldings that hold the PVC window frame inside the old wooden frame. Originally, the old sliding aluminum windows were installed in that wooden window frame. Without that PVC flashing covering that caulked gap, if the caulk fails then rain water can get in between the PVC and the window stop molding causing the existing wooden window frames to rot. The 1 1/2 inch PVC flashing acts as an umbrella or roof so that even if the caulk fails, no rain water gets in where it shouldn't/

I am currently in the process off removing all the narrow (1 1/2 inch wide) PVC flashings (of the kind you see in the photo) and replacing them with 3 inch wide PVC flashings that protect the entire bottom of the wooden window frames from exposure to rain or Sun. That keeps the paint on these window frames in the shade 24/7, and that keeps the paint from cracking and peeling, and that in turn makes these windows essentially maintenance free (even though the frame is just painted wood).

I'm also using Kop-R-Lastic to hold the new wider 3 inch plastic flashings in place in exactly the same manner. If the Kop-R-Lastic doesn't hold, then I am facing the possibility of having to replace 66 rotted wooden window frames. That's cuz I really only get a chance to inspect the windows when tenants vacate, and often tenancies will last 5+ years. If there's a problem, and I don't find out about it for 5 years, it's often too late to fix. And, the wooden window frames in my walls are COMPLETELY different than the kind of windows you install in a house. My windows have wooden rails nailed into their outer periphery that fit between the concrete block and brick wythes of my 18 inch thick brick veneer walls. So, they are VERY much more difficult to remove than the windows in a house. You literally hav to cut the wooden frame to pieces to remove it from the building wall, OR remove the brick veneer from around the window.

Obviously, I have a great deal of confidence in the Kop-R-Lastic caulk I'm using to keep the new 3 inch flashings in place so that rain water doesn't get in where it shouldn't. I wouldn't use Kop-R-Lastic if I wasn't confident it was up to the job. If it fails, it could result in my having to replace all my wooden window frames with new ones or PVC ones, either option costing well over $50,000. My building is my pension and old age security. I'd be a fool to gamble with it. I've got enough experience with Kop-R-Lastic that I'm not worried. It will easily serve as a long lasting putty on multipane windows.


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