windows
About 10 years ago I had all the windows in my apartment replaced. Four or five years later, when I would open them to insert a fan or an air conditioner, the top window would slide down 6-12 inches in a few of the windows. Is there anything that I can do to adjust the windows so they don't slide down?
[update]
I got a couple good answers for wooden windows. Can anything be done with metal?
I would recommend you just make the Window screen yourself. They are really easy to make and I am sure you can find a clip option that will fit your needs. Besides, if these are contractor windows, you probably can't get the OEM screen anymore and/or the manufacturer no longer exists.
Here is an example screen parts supplier: http://www.qualitywindowscreen.com/screening-supplies-parts-tools.html
Here is an example video showing how easy the screens are to build: https://www.youtube.com/watch?v=MxZHslZduRw
The usual approach is a "crank-type" casement window with a loop in place of the crank handle, and a hook on a pole (try "clerestory pole crank" as a search term) that engages the loop. There are also hex-type versions that use a flexible shaft inside the pole. Or, these days, motors. I'd suggest the hook on a pole, I view motors in this sort of application as things likely to fail and then make the motorized windows useless as they will probably be hard to replace when they fail. Or they'll leave you with inoperable windows during a power outage.... But it is an option.
A hook or hex style operator pole (image from BlaineWindow.com):
I can't make out how the current windows are operated - they might be able to be retrofitted with operators of that type, rather than replacing the whole window, if the only reason for replacing them would be to make them operable from below.
The style that @TDHofstetter mentions, with a catch that's operable by a hook (image from calaifornia-classics.com):
Best Answer
The counter balance is not working correctly, but repairing this or replacing it is non-trivial. Instead, you can pickup a device like this that will create enough friction to hold the window in place. It should be installed between the window and the frame and is a simple DIY job.
http://www.lowes.com/pd_128860-76018-F+2537_0__?productId=3010767