Good call on the breathable barrier, but honestly, I've found that proper venting makes even more of a difference. Had a client last year who went all-in on sealing every joint perfectly (like textbook-perfect), but still had moisture issues because the airflow underneath was terrible. Once we got some decent venting sorted, the problem disappeared completely. Definitely don't skimp on sealing, but getting that airflow right is just as critical in my experience...
Haha, venting strikes again, huh? Ever notice how airflow is like the unsung hero of roofing? Everyone's always obsessing over sealing and barriers (which are super important, don't get me wrong), but airflow just quietly saves the day. Had a similar situation after a storm last spring—client was convinced it was all about sealing tighter, but nope... vents to the rescue. Glad you got it sorted out though—feels good when you finally nail down the real issue, doesn't it?
Totally agree about airflow being underrated—it's like the drummer in a band, nobody notices until it's off. Had a similar scenario recently, client was convinced insulation thickness alone was gonna fix their moisture issues on a modified bitumen roof. But after checking it out, turns out their venting was practically non-existent. Once we adjusted that, problem solved itself pretty quick.
Speaking of insulation though, curious what you guys think about polyiso vs EPS under mod bit? I've seen mixed results depending on climate and roof setup. Polyiso seems great on paper, but I've heard it can lose some R-value in colder temps. Anyone have experience with that?
Had a similar issue last winter—client went all-in on polyiso thinking it'd be the silver bullet. Worked fine most of the year, but when temps dropped below freezing, we noticed some performance dips. EPS might not have the highest R-value upfront, but at least it's consistent. Polyiso's great in moderate climates, but in colder areas...I'd stay skeptical. Seen too many "paper-perfect" solutions not hold up in real-world conditions.
Had a similar experience myself a couple years back. Went with polyiso thinking it'd be the best bang for the buck, but once January hit and temps dropped, I noticed my heating bills creeping up again. EPS might not win any awards on paper, but at least you know what you're getting year-round. Learned my lesson—sometimes the "boring" option is the safest bet, especially when winter decides to throw a tantrum...
