Good question—roof slope and orientation definitely play a role. I've inspected plenty of homes where north-facing roofs or shallow slopes had noticeably worse ice dam issues. North-facing sides get less sun exposure, so snow sticks around longer, melts unevenly, and refreezes at the eaves. Shallow slopes slow down runoff, giving water more time to freeze up again.
Funny enough, I once checked out two identical houses side-by-side—same insulation, same venting—but one faced north and had a gentler pitch. Guess which one had the ice dams? Yep, the north-facing one with the lower slope. So yeah, insulation and ventilation are key, but roof orientation and pitch can definitely tip the scales.
Interesting points, but honestly, I'm not totally convinced orientation and slope are as critical as you're suggesting. When I bought my first house, the inspector made a huge deal about north-facing roofs and ice dams, so I was pretty worried. But after adding extra insulation and improving attic ventilation, I haven't had any issues—even with a shallow, north-facing roof. Maybe orientation matters, but from my experience, proper insulation and airflow seem to make a bigger difference overall.
"Maybe orientation matters, but from my experience, proper insulation and airflow seem to make a bigger difference overall."
Totally agree with this. When I redid my attic insulation last year, I noticed an immediate improvement—less ice buildup and lower heating bills. Orientation might have some impact, but good ventilation and insulation definitely seem more practical overall.
I see your point about insulation and airflow making a bigger difference overall, but I wouldn't completely discount orientation either. A few years back, I managed a property where the roof faced directly south, and even with decent insulation, the attic got incredibly hot in summer. We ended up installing additional vents and reflective barriers to manage the heat better. It helped a lot, but honestly, the orientation definitely made things trickier than usual.
That said, proper insulation and ventilation are still key—no argument there. I've seen plenty of buildings with poor ventilation end up with mold issues or ice dams, regardless of how they're oriented. So yeah, orientation matters a bit...but if you're choosing between rafters and trusses, I'd focus more on how easily you can maintain good airflow and insulation quality in your design.
Good points all around. I've noticed that trusses can sometimes make it trickier to retrofit additional ventilation later on, especially if you realize down the road that your airflow isn't quite cutting it. Rafters seem a bit more forgiving in that sense, since you have more open space to work with. Curious though—did you find reflective barriers made a noticeable difference right away, or was it more gradual? I've heard mixed things about them.
