What if some of these water blisters appear in inside clad walls? I'm wondering if the weight from the ice storm of two years ago could be the culprit? That is when these "blisters" started to appear. What if I removed the drywall screws or nails and replaced them with fresh ones an inch or so away. Wouldn't it be better making new holes so that it wouldn't loosen as easily? Also, just to make you feel old, I recall back in the late 70's when you were a guest on radio in Cornwall, Ontario several times at CFLG-FM.
Answer:
If the ice storm of two years ago was the problem, it had a more drastic effect on your house than on any of the others from this point of view. I can accept that the interior walls were inundated with water and since then, the nail heads had little to do but rust. Rust, as it turns out, expands the cavity it occupies. That means that your idea just might work but before going to a great deal of trouble, I think I'd want to try it on one wall and leave it for a season or so.
