Mapping out the vents ahead of time really does make a difference, especially if you’re dealing with an older house where things might not be up to code. I’ve run into situations where folks added spray foam without considering how it would affect attic ventilation, and it ended up trapping moisture instead of solving the problem. Sometimes, a hybrid approach—using spray foam in the tricky spots and batt insulation elsewhere—works best, but it depends on the roof structure.
Curious if you’ve looked into whether your current roof has any hidden issues like ice damming or blocked soffit vents? Those can sneak up on you and undo a lot of good work if they’re not addressed during the replacement. Every roof seems to have its own quirks... I once opened up a 1920s bungalow and found three different types of insulation layered over the years. Took some creative problem-solving to get it right.
I hear you on the attic ventilation—my place is only about 30 years old, but I still found some weird stuff when I started poking around.
That’s what I’m leaning toward too, since I don’t want to mess up airflow. I did check for blocked soffit vents and didn’t see anything obvious, but is there a way to know for sure without tearing everything apart? Ice damming hasn’t been a problem yet, but I’m not sure if that’s luck or decent insulation. Anyone ever regret using spray foam in certain spots?“Sometimes, a hybrid approach—using spray foam in the tricky spots and batt insulation elsewhere—works best, but it depends on the roof structure.”
NEED ADVICE ON REPLACING AN OLD LEAKY ROOF
If you want to check your soffit vents without turning your attic into a demolition zone, try this: on a sunny day, kill the attic lights and look for daylight coming through the soffits. No light = probably blocked. You can also hold a tissue up near the vent from inside—if it barely moves, airflow’s weak. I went with spray foam in my knee walls and regretted it later when I needed to run new wiring... that stuff does NOT want to come out. Wouldn’t do it again in spots where I might need access.
I went with spray foam in my knee walls and regretted it later when I needed to run new wiring... that stuff does NOT want to come out.
- Spray foam’s a beast for future access, totally agree. I’ve seen a few projects where folks had to literally cut out sections of wall just to fish new lines.
- When you’re planning the roof replacement, are you thinking about upgrading insulation or just sticking with what’s there? Sometimes it’s worth opening things up while you’ve got the chance, but it can get pricey.
- Curious if you’ve checked the condition of your roof decking yet? If moisture’s been an issue for a while, sometimes the rot goes deeper than expected.
I ran into the same issue with spray foam when I remodeled my attic a couple years back. It’s great for air sealing, but man, if you ever need to get behind those walls again, it’s like chiseling through rock. When I did my roof, I took the chance to pull up a few decking boards and check for rot—turned out some of the sheathing was worse than I thought. If you’re already opening things up, it’s worth poking around before sealing everything tight. Sometimes you find surprises you’d rather deal with now than later...
