I've heard, on your show, the solution to sealed(not)window leakage, however, since I didn't have the problem at the time I didn't pay enough attention. I now have the problem. Our 9 year old windows are starting to lose their seal, one in the living room and two in the garage. The living room window is a crank out that is under warranty but the manufacturer is out of business. I know you talked about drilling the unit somehow to permit air flow but I don't remember where and how.
Answer:
In some cases windows have lost their thermal seals. If there are certain gasses in a particular unit and the seal has been gone for some time, streaks may be quite permanent. If, on the other hand, the seal depends on a vacuum, it can often be corrected without having to replace the complete unit. Rather, by removing the window and drilling 3/16” holes along the top down through the frame and metal spacer between the sheets of glass. Now turn the window over and do the same thing along the bottom. The holes are 3 to 4 inches in from the ends. You can then re-install the window and drill the same sized holes in the frame horizontally from the outside to meet the vertical ones. The latter should be sloped slightly upward and all you have to do from there is fill them with non-corroding steel wool. This will permit air to pass but insects won’t get in.
Window cranks should only be used to bring the windows in far enough for the locking mechanism to catch. Forcing cranks beyond that causes excessive stress on the mechanism and quickly weakens it in that area.
