I Need A Taller Sill Expander!

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I Need A Taller Sill Expander!

#1 Post by DerbyDad03 » Wed Aug 29, 2007 2:35 pm

I'm installing some Simonton windows and I've hit a snag.

I want to raise the window up so I can avoid using the head expander.

When I raise the window high enough so that it is behind the upper stop, the sill expander that snaps into the bottom exterior of the frame is off the sill by about 3/8". (My sill angle is about 15 degrees.)

I called Norandex and they said that they don't make a taller sill expander for the Simonton windows.

Any suggestions? I'd really like to avoid using the head expander if possible.

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Windows on Washington
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#2 Post by Windows on Washington » Wed Aug 29, 2007 7:16 pm

Sounds to me as if your windows may have been ordered a tiny bit short. This is not typically an issue because the coil stock is usually capped right to the window and the sill angle can be bypassed.

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#3 Post by DerbyDad03 » Wed Aug 29, 2007 9:45 pm

I'm taking off the storms and painting the exposed wood, not wrapping it.

The windows were measured just inside the sill and made 1/2" shorter than the rough opening. That measurement seems to be correct, but had I thought about not using the head expander before hand, I would have added a 1/2" to my RO measurements.

I'll admit it, probably a rookie mistake, but I just followed the various directions I found for measuring windows. For example, at

http://www.buzzle.com/editorials/10-17-2004-60543.asp it says:

"If your window sill outside slopes downward for water drainage, you have to make sure that you measure from the HIGHEST point of the sill."

Anyway, I (temporarily) installed 1 (of 9) windows today and this is what I did:

I screwed a 1/2"x 1/2" piece of stock to highest point of the sill so that the top of the window is behind the upper stop - no head expander needed.

I then ripped a piece of 1/4" x 1 1/2" vinyl lattice in half and tacked it to a piece of 3/4" stock which was ripped at 15 degree angle and the correct height to support the front of the window. I then screwed that to the sill just inside the side stops. Now when I snap the vinyl sill expander into the track on the window, it will be tight against the vinyl strip that now hides the gap, while the wood prevents to bottom sill from flexing. My next step is to insulate under the window, install backer rod along the top and sides and then caulk, caulk, caulk.

Yes, there's some extra work required, but it'll be worth it not to see the head expander.

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#4 Post by Guy » Thu Aug 30, 2007 6:19 am

DerbyDad, don't beat yourself up on a mistake that's made all the time. Most of us never use the head expander for the same reason you've found. It looks horrible and throws the inside of the window away from the stop at the top of the opening. It's a waste of vinyl as far as I'm concerned. You would never have known about this unless someone had told you previous to your measuring. There are a couple ways to attack this issue with quick results. You can extend your stop in the head of the old frame with another piece of matching wood. This would require staining or painting to match the existing color. In most cases it would never be seen because most window treatments cover the top of each window. This wouldn't be my first choice to make though.

The second choice would be to attach an extension to the sill for your sill angle to work properly. We've done this method a couple times with old windows that have a sill angle larger then the industry standard. The funny thing is you have the pieces to fix this right in front of you. The head expander can be cut to fit across the sill. It's also the same color as your window and it doesn't have to be painted. Cut the head expander down the middle the long way (so you have two pieces that form 90 degree angles. You can then shorten the legs until it lies across the sill giving you the required lift. If you make one leg a 1/2" and the other 1" it usually lies in there pretty good. Lay the piece in with the longer leg facing upward like a table top with the short leg facing out of the opening. You can make it longer than the distance between the stops at the bottom. This way you can notch the ends to go around the stops until it comes flush to the outside. Now you should be able to set your sill extender on top of this and seal them up.

Hope this makes sense! Sometimes it's difficult to explain things with out showing you. Hopefully it's understandable for you. Good Luck!!!

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