My parents have a bunch of Anderson 400-series windows in a sun porch. Below are pictures showing the problem. The windows are no longer hung straight, causing them to drag on the frame and become very hard to close. In the picture, there are four windows in groups of two (the right two are a set, the left two are a set)

I am not sure how just one window of each set doesn't work properly, especially because the entire unit is attached to the house via a nail flange on all four sides of the window.

What can I do to fix these windows so they operate as they're supposed to?

Please let me know what information I've left out that might be useful.Windows

Single Window

  • 2
    I am not sure if it is the picture or not, but the window trim looks arched in the middle. If it really is arched then the framing under the window is likely arched also. This needs to be inspected. If this is the issue is just the framing warped or does it transition down to the ground. Commented Sep 20, 2016 at 17:56
  • What type of foundation or support system is the porch resting on? Is it on a slab, raised deck, concrete piers??
    – mikes
    Commented Sep 20, 2016 at 21:12
  • It's sitting on a "normal" foundation...it's 8" concrete block that goes down to a footer (I don't know for certain how deep)
    – Carl
    Commented Sep 21, 2016 at 10:54

2 Answers 2


First I will answer the question. Remove the window and reinstall it. You may need to adjust the lower sill or cut a little out of the header at the top to get it to set level. It is a non bearing wall so a 1/2" off the header will not matter. The sill will not have any extra material to cut out. Or you could simply resquare the window and let it run downhill like it already is.

You will not be able to trim any of the window sash to get it to fit back in without destroying the vinyl cladding, so it has to be reset.

Now for the real issue. The picture does not reveal any other symptoms but I will tell you what I see going on with the window

The wall to the left has settled for some reason, if it was originally a porch and not a living space, it may have not been structured the way a living space is needed. Either the footings where not sized properly and the footer settled down some or perhaps termites or carpenter ants got in there and caused some settling.

I would consider doing something with that, and it may not crack the window on it way back up, but when the window is corrected it will stay.

  • It was always built as a porch...my parents had it built around 1984 to prevent freezing of the water lines that were ran on the outside wall of the house. I have heard the need to remove and reinstall the windows before, but was trying to avoid doing so because of the amount of work. I'd have to remove the trim, cut the nail flange, then attach the windows via screws through the inside of the windows.
    – Carl
    Commented Sep 21, 2016 at 10:55
  • You will not need to cut the all important nail flange. Remove the wide trim around the window, cut back the siding away from the window 2" back setting you saw to the depth of the siding. This will allow you to remove the nails from the flange. Of course, you will need to remove the trim from the inside too.
    – Jack
    Commented Sep 21, 2016 at 14:35
  • This is what I ended up doing and worked perfectly.
    – Carl
    Commented Sep 27, 2016 at 12:33

I have had this same problem at my mother in law's house.

A simple adjustment of sash arm was how I fixed it. Here is the video of how to adjust the sash arm.


  • I like the simplicity of it, but I don't think the windows in question have this feature...I will definitely double check though.
    – Carl
    Commented Sep 21, 2016 at 10:58

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.