Finally Got My Attic to Stop Sweating - Soffit Vents Did the Trick

Has anyone tried mixing both types - like rigid in the easy spots and flex where it gets weird? Or is that just asking for trouble down the line?

- I actually did a combo last year - rigid baffles where the rafters were straight, flex in the tight corners.
- No issues so far, but I did notice the flex ones sagged a bit after a hot summer. Not a dealbreaker, just something to watch.
- If you seal the seams where they meet, it seems to keep airflow decent.
- Honestly, I’d do it again. Full rigid would’ve been way more expensive and a pain to install in my weird attic angles.
- Just my two cents, but mixing isn’t as risky as some folks make it sound... as long as you’re careful with the install.

Mixing rigid and flex baffles actually worked out for me, too. I used rigid along the main runs, then switched to flex for the oddball corners where nothing else would fit. The only hiccup was making sure the overlap at the seams didn’t leave gaps - used a bit of foil tape and it held up fine through last winter. One thing I noticed: the flex baffles do tend to sag if they aren’t supported well, especially in spots with wider rafter spacing. If I did it again, I’d probably add a few extra staples or maybe some wire to keep them from drooping. Otherwise, airflow’s been solid and no more condensation issues so far. Mixing seemed like the only practical way in my attic’s weird layout... I don’t see any big downside as long as you pay attention to sealing and support.

The only hiccup was making sure the overlap at the seams didn’t leave gaps - used a bit of foil tape and it held up fine through last winter.

I’ve run into that same issue with flex baffles sagging, especially in older homes where rafter spacing is all over the place. Ever try using those metal insulation supports? They’re cheap and work pretty well for keeping things snug. Curious if you noticed any difference in attic temps after sealing everything up tight? Sometimes folks worry about overdoing it and losing some ventilation, but sounds like your airflow’s still good.

Curious if you noticed any difference in attic temps after sealing everything up tight? Sometimes folks worry about overdoing it and losing some ventilation, but sounds like your airflow’s still good.

I had the same concern when I first started sealing up gaps - worried I’d end up with a stuffy attic and just move the moisture problem somewhere else. Used those metal supports too, actually. They’re a lifesaver for keeping batts from drooping, especially in weirdly spaced rafters. After I got everything snug and taped, attic temps actually evened out a bit - less wild swings between day and night. Didn’t notice any musty smell or condensation this winter, so I guess the soffit vents are doing their job. Still check every few weeks just in case, though. Old habits...

I get where you’re coming from - tightening up the attic always makes me nervous about trapping moisture, especially in older houses. When I did mine, I went step by step: first sealed the obvious gaps, then checked airflow with a smoke pencil (cheap but surprisingly helpful). I was skeptical about whether the soffit vents would be enough, but after a winter and a humid spring, no musty smell or damp insulation so far. Temps are definitely more stable, but I did notice it gets a bit warmer up there on sunny days than before. Not sure if that’s just the insulation doing its job or if I need to add a ridge vent down the line.

One thing I learned the hard way - don’t block those soffits with insulation. I had to go back and fix a couple spots where the batts slid over the vents. Metal supports help, but I ended up using baffles too, just to be safe. Still, I’m not convinced every attic needs to be sealed up like a submarine... sometimes a little draft isn’t the end of the world.