Last winter, I've had some issues with ice dams on my roof. I live in a townhouse in Southern Quebec, Canada, in the middle unit, where lately temperatures during the winter can go anywhere between -40C to 10C.
So this year, I've decided to go look in the attic. There was a lot of insulation missing near the eaves and the space was pretty warm. I spent an afternoon in there filling the gaps, and insulating some exhaust pipes that needed it. I managed to drop the temperature by a good 7 or 8 degrees Celcius, so I figured it would be enough.
Today, it's about -7C and cloudy with a bit of snow. I went to double-check that my changes were good. I found that sure enough, the temperature has dropped below freezing for the most part (figure #1). However, both the sidewalls - made of brick - are still pretty warm (figures #2 and #3).
So my first question is, I'm assuming that both my neighbors have similar insulation issues in their attics and that their warm air is leaking in my attic, am I right?
Assuming that's the case, and that I cannot get either or both of them to fix the issue on their end, is there anything I can do on my end, and should I? If so, what is it and how much work would that be?