Tag Archives: window

Window aluminum cladding

The 2nd floor windows were installed and air sealed, but still needed some protection from the elements. In short, I needed to add some aluminum cladding to prevent bulk water from seeping in around the windows.

I had an interesting experience when I had the aluminum cladding added to our 1st floor replacement windows. I learned that this job requires attention to detail and a specific skill set: Taking accurate measurements.

The contractor I hired for the 1st floor windows was somewhat deficient on both, so I ended up finishing the job myself. With that I felt fairly confident to take on all our 2nd floor windows … except that they are just a little higher off the ground. But that wasn’t a problem. I put up scaffolding so I had a safe working platform 20 feet off the ground.

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I bought two coils of sheet aluminum, a bunch of caulk, and rented an aluminum brake (also called siding brake). Because of the elevation I moved slowly but deliberately. I have to admit, it was rather exhausting because of the concentration and focus it took. But after four days of measuring, cutting, bending, trimming, fitting, and caulking, I had all windows cladded. Again, just in time for the winter season. Hurray!

Related posts:

2nd floor replacement windows

1st floor window cladding – or cluster

1st floor replacement windows


2nd floor replacement windows

My entrance into the world of energy efficient yet affordable windows started with a lot of research, and I mean a LOT of research. I had to acquaint myself with new vocabulary like “triple pane insulated glazing units,” or “solar heat gain coefficient.”

But it was worth it and it paid off. The replacement windows for the basement and 1st floor have served us well. They kept us comfortable on even the coldest days and keep our heating bills low.

I was very happy to tap into my acquired expertise again, this time to get our 2nd floor replacement windows installed. This time around it was a breeze, because our friend Drew and I had already done all the prep on the second floor window bucks a while back.

And on the purchasing side, I went around to check the specifications, performance values, and prices on triple pane insulated glazing units from local manufacturers. And I found what I was looking for – energy efficient windows that did not break the bank.

How did I know that I was looking at high performance windows? The National Fenestration Rating Council (NFRC) developed a national rating system for windows so that a consumer can compare apples to apples.

window-45 window-46

  • U-factor: 0.17
  • Solar heat gain coefficient (SHGC): 0.20
  • Visible transmittance (VT): 0.35
  • Air leakage (AL): ? 0.3 cfm/sf
Fixed casement
  • U-factor: 0.16
  • Solar heat gain coefficient (SHGC): 0.24
  • Visible transmittance (VT): 0.42
  • Air leakage (AL): ? 0.3 cfm/sf

I have written a lot about what these performance values mean, and rather than repeating myself let me link you to one blog post that summarizes the tech talk, or you can click on any of the other links in this blog post.

One thing that I will repeat – because it can’t be said often enough – is the importance of the air leakage metric. Why? Because any insulation is only as good as it is airtight. Take, for example, a ski jacket on a downhill slope. You left the front zipper partially open. Will the jacket keep you warm? No, because the cold air gets in. Same with windows.

The Efficient Window Collaborative recommends windows with an AL of 0.3 cfm/sf or less. A value of 0.3 cfm/sf is like a ski jacket with the zipper partially open. You really want to zip it up. Our target was a value of 0.05 cfm/sf or less.

Our NFRC label says less than or equal to 0.3 cfm/sf. However, to be certain about the actual performance, I asked the manufacturer for the test reports and found that they listed the actual air infiltration at 0.02 cfm/sf. Bingo!

Please note that most labels do not list the actual air leakage value. You will have to ask the vendor for the test data. It is probably the best question you will ask.

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I am just happy that we got the old double hung windows out and the replacement windows in before the winter hit. It will cut down on the heat loss, and changes the look from an abandoned apartment to something resembling a home.

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Windy windows with a warp

I bought our 1st floor windows locally, at Newtec Windows & Doors at 36th Street and Kedzie here in Chicago. I liked their pricing. But first and foremost, I liked their specs. Their awning and casement windows in the 1400 Series are advertised as almost airtight. What I don’t like is that the casements I bought have major air leaks and that the service response by Newtec is painfully slow (and that is putting it politely).

It was about a year ago when I ran into trouble. Once it got cold and windy outside, I noticed drafts around our casement windows, which should not have been there at a specified air leakage of 0.02 cfm/sf.

Newtec Windows & Doors attempted to fix the leaks twice to no avail. The service visits were followed by two inspections by the company owner with his product suppliers. The verdict each time was that the casements had a very slight bow to them at the corners.

window-36 window-37

If I measure the gap between the sash and casement where it closes and seals properly, I get a reading of 1/16 inch. Toward the corners, where the casement bows out, the gap widens to 1/8 inch. At this point the casement doesn’t press into the rubber gasket of the sash anymore, thus the air leak.


Putting a straight edge along the casement bottom is another way to reveal the bowing and the subsequent widening gap.

The vinyl profiles of the 1400 Series are manufactured by Rehau. During the last inspection (March 2015) the Rehau representative recommended that we replace the existing gaskets with new ones that would bridge the gap and provide the required air seal.

Ten months later, I finally got Newtec to come out to install the new gaskets – but it took some serious nagging!

The service technician pulled the old gaskets out, installed the new gaskets…

window-39 window-40

… and the windows were leaking air like they did before.

The old and new gaskets have an identical profile. To bridge and seal the gaps at the corners, the new gasket would need to have a profile at least 1/16 inch deeper – demonstrated here by squeezing the gasket.


Now that we have exhausted the gasket option, I wonder what is next. Replacing the bowed casement portion of the windows with one that is straight? But what I wonder about even more is when I will see the next effort to fix this by Newtec Windows & Doors.

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Inspecting windows

I had a couple of visitors this morning: The president of Newtec windows and a technical expert from the manufacturer that supplies Newtec with the vinyl moldings.

I again got my smoke pen out so that we could take another look at the air leakage of the 1st floor casement windows. I didn’t need the smoke pen. I actually barely got to the window. My visitors took the window seat and carefully inspected the corners, with the windows closed and open.

We quickly agreed that the corners are the problem. We identified an increasing gap between frame and casement in the corner when the window is shut and locked.

The frame has a set of inner and outer gaskets. When the window is shut and locked, the casement is supposed to press into the gaskets, which would provide the specified air seal.

window-34 window-35

However, with the increasing gap in the corners, the gaskets and casement are not in full contact, thus the air leakage.

Very good. We have identified and agreed on what the problem is and that it needs to be fixed. My visitors took that information with them, and promised to get back to me in due course with a solution. I guess there are a couple of ways to go about it and I am really interested to hear how they plan to plug the gap. Stay tuned!

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Adjustment attempts

Checking on casement corners

Breeze hunting

1st floor replacement windows

The world of windows

Blower door test – after insulation


Adjustment attempts

Buying local pays off: If there is a problem with the purchase, it is easy to get face to face with your vendor!


Our 1st floor replacement windows were manufactured by Newtec around 2 ½ miles down the road from us. Once I had tied the air leakage problem to our casement windows I jumped in the truck and paid Newtec a visit. I was hoping for some kind of technical fix. May be a replacement gasket that would stop the air leaks in the corners of the operable casements?

It turned out that the gaskets are molded into the window profile and cannot be changed. But the window locks can be adjusted to pull the casement closer into the frame.


I gave that a try and I believe this reduced the air leakage on the lock side, at least a little – but not enough. Adjusting the locks had, however, no effect on the opposite hinge side. Those corners remained drafty cold air highways.

I reported back to Newtec, who arranged for a service technician to visit and take a look in order to fix the casement windows.

He also tried to adjust the the locks, but was no more successful than I was.

On the hinge side, he installed a set of latches that should pull the casement closer into the frame upon closing.


That didn’t lead to any improvements, either. He consulted with his headquarters and I was told that the problem appears to be with the hinges. They are sticking out just a notch too much and prevent the casement gaskets from sealing up against the frame.

Newtec couldn’t offer an immediate solution to the problem, but wanted to get the technical experts together and have them take a look at the windows. They will be knocking at my door in a couple of days and I am curious to see what they have to offer.

Related posts:

Checking on casement corners

Breeze hunting

1st floor replacement windows

The world of windows

Blower door test – after insulation