- I get where you’re coming from, but I’ve seen a lot of folks in my area (southern NH) go overboard with attic ventilation and end up with other headaches.
- Too much airflow can actually pull warm air from the house into the attic if the air sealing isn’t solid, which just feeds the ice dam cycle.
- I’ve inspected homes where people added extra roof vents thinking “more is better,” but it just made the attic colder and didn’t solve the moisture issue—mainly because the real culprit was leaky ceiling penetrations (can lights, bath fans, etc).
- I’m not saying skip ventilation—just that it’s gotta be balanced with proper air sealing first. Otherwise, you’re just moving the problem around.
- On bath fans, totally agree: venting into soffits is a recipe for trouble. I’ve seen moldy sheathing right above those spots more times than I can count.
- For me, best results come from:
- Meticulous air sealing (even if it’s a pain)
- Making sure baffles keep soffits clear
- Only adding more vents if you’re sure the attic isn’t already losing too much heat
- Every house is different, but I’d rather fix the leaks before cranking up the airflow. Just my two cents...
Can’t tell you how many times I’ve walked into attics where someone’s gone wild with roof vents thinking it’ll solve everything, only to find frost on the nails and insulation looking like Swiss cheese. It’s like playing whack-a-mole—fix one thing, another pops up if you don’t get the air sealing right first.
Totally agree about bath fans into soffits. That’s just asking for trouble. I’ve seen plywood delaminate and even mushrooms (yep, actual mushrooms) growing on sheathing in a couple spots where bath fans dumped warm, wet air right under the eaves. Not exactly the kind of attic ecosystem you want.
I get why folks want to add more vents—seems logical on paper—but if you’ve got can lights or attic hatches leaking air, you’re just making your attic a freezer and still dealing with ice dams. I usually tell people: air seal first, then check if you actually need more venting. Sometimes less is more, especially in these old New England homes with all their quirks.
I keep hearing “air seal first,” but how do you actually know if you’ve got enough of it? I mean, I’ve caulked around the attic hatch and stuffed insulation around the can lights, but I still get a bit of frost on the nails when it’s really cold. Is that just normal for these old houses, or am I missing something? I’m also a bit skeptical about paying for a blower door test—worth it, or just another thing contractors try to sell? My budget’s tight, so I’m always weighing what’s actually going to help.
I’ve caulked around the attic hatch and stuffed insulation around the can lights, but I still get a bit of frost on the nails when it’s really cold. Is that just normal for these old houses, or am I missing something?
Had the same thing in my 1950s place—frosty nails every January. I thought I’d sealed everything, but turns out there were gaps I couldn’t see (like where wires poke through top plates). I was skeptical about the blower door too, but honestly, it found leaks I’d never have guessed. Not saying it’s a must, but it did help me focus my efforts. Still, some frost is just part of old houses unless you gut the whole attic, which...yeah, not in my budget either.
Yeah, I get a little frost on the nails in my attic too, even after sealing up what I could find. Some of it just seems unavoidable in these older places. As long as it’s not dripping or causing stains, I try not to stress about it too much.