Materials help, but airflow’s what really keeps things dry and cooler.
I used to think just picking the “best” underlayment would solve everything, but nope—my attic was still roasting. Ridge vents made a huge difference, but I also added soffit vents after reading up on it. Honestly, I’d argue airflow is 70% of the battle, especially in humid climates. My neighbor skipped the venting and now he’s got mold issues... not worth it.
You nailed it—airflow is huge, and people overlook it all the time. I made the same mistake early on, thinking a pricier underlayment would be a magic fix. It helped with leaks, but didn’t do much for attic temps or humidity. Once I put in continuous soffit vents and a ridge vent, the difference was night and day. The attic actually felt like part of the house instead of a sauna.
I’m in the southeast, so humidity’s always lurking. Even with good materials, without proper venting, moisture just gets trapped. I’ve seen neighbors replace decking way too soon because mold took over. Materials matter for sure—especially if you’re dealing with ice dams or heavy rain—but airflow’s what keeps everything working long-term.
Kind of funny how something as simple as moving air around can save you thousands down the road... Glad you figured it out before it turned into a bigger headache.
You’re spot on about airflow—people get fixated on the latest underlayment or shingle tech, but if the attic’s not breathing, you’re just asking for trouble. I’ve seen plenty of roofs with top-tier synthetic underlayment still end up with warped decking and mold because the vents were either blocked or undersized. In my area (Midwest), ice dams are a bigger headache than humidity, but the principle’s the same: trapped moisture is going to find a way to cause damage.
Curious—did you notice any difference in your energy bills after adding the soffit and ridge vents? I’ve had clients report their AC runs less once the attic temp drops, but it’s not always dramatic. Also, what kind of underlayment did you end up using? I’ve had mixed results with some of the newer synthetics—great for installation speed, but not always as durable as advertised when it comes to long-term adhesion or tear resistance after a big storm.
I’ve had mixed results with some of the newer synthetics—great for installation speed, but not always as durable as advertised when it comes to long-term adhesion or tear resistance after a big storm.
That’s exactly what’s been bugging me about the synthetics. I put down a “lifetime” synthetic underlayment (forget the brand, but it was one of the big box store ones) about six years ago, and after a couple of those Midwest windstorms, I found spots where it had started to peel up at the edges. Not catastrophic, but enough to make me question if the extra cost was worth it over the old-school felt. I get that it’s lighter and easier to work with, but if it can’t handle a few seasons of wild weather, what’s the point?
On the venting side, I did notice my upstairs stayed cooler after adding ridge and soffit vents, but my energy bills didn’t drop as much as I hoped. Maybe $10-15/month in peak summer? Not nothing, but not game-changing either. Still, the attic feels less like a sauna now, so I figure that’s gotta be helping with shingle life and keeping the decking in better shape.
Curious if anyone’s tried those peel-and-stick underlayments? I keep hearing they’re the gold standard for ice dam areas, but I’m skeptical about how they hold up long-term—especially if you ever need to do repairs. Do they actually stay stuck, or do they end up bubbling and peeling like some of the cheaper synthetics? And what about removal—are you basically married to it once it’s down?
I’m starting to think there’s no perfect solution—just trade-offs depending on your roof and climate. Would love to hear if anyone’s found something that actually lives up to the hype, especially in places where you get both crazy heat and ice.
I’ve used peel-and-stick on a couple of projects in ice dam country (northern MN), and honestly, it’s a mixed bag. It sticks like crazy—almost too well if you ever have to pull up a section for repairs. Never had bubbling, but removal is a pain and usually takes some decking with it. For areas that get hammered with ice and snow, I’d still pick it over felt, but I wouldn’t do the whole roof with it. Just the eaves and valleys. The rest I stick with a more breathable synthetic, even if it’s not perfect.
