best spot for ice barrier under shingles?

"Maybe it depends more on the roof angle or local climate conditions rather than just defaulting to always putting it in valleys?"

Yeah, that's pretty much my experience too. I've skipped ice barrier in valleys before when the pitch was steep, and it's been fine for years. But honestly, if you're in a region with heavy snow or frequent freeze-thaw cycles, I'd err on the side of caution. It's cheaper than dealing with leaks later... Learned that lesson the hard way once!

Yeah, totally agree - roof pitch makes a big difference. My place has a pretty shallow slope, and even with moderate snow, ice dams formed way quicker than I expected. Ended up adding extra barrier after the first winter...lesson learned.

Yeah, shallow roofs can be tricky... Did you end up running the barrier just along the eaves, or did you go further up the slope? I've seen some folks extend it higher - wondering if that makes a noticeable difference in preventing dams.

"I've seen some folks extend it higher - wondering if that makes a noticeable difference in preventing dams."

Honestly, I tried extending mine higher up the slope once, thinking it'd help. Didn't see much difference, and it really stretched my budget. IMO, proper attic insulation and ventilation did more to prevent ice dams than extra barrier coverage ever did...

- Yeah, same experience here - putting extra barrier higher didn't seem to do much.
- Wonder if there's a point of diminishing returns on height placement?
- Agree on ventilation and insulation being key, but I'd also add roof pitch into the mix.
- Had a neighbor with a steeper slope who never got ice dams, even with minimal barrier.
- Makes me curious if slope angle plays a bigger role than we think...
- Also, proper gutter maintenance seems underrated - seen some nasty dams from clogged gutters alone.

I've seen steep roofs with pretty bad ice dams too, so I'm not totally sold on pitch alone being a magic bullet. Sure, it helps shed snow faster, but if your attic insulation or ventilation is poor, you're still gonna have issues. Totally agree on gutter maintenance though - seen way too many cases where just cleaning out leaves would've prevented a mess. I'd say barrier placement matters, but focusing solely on height might be missing the bigger picture...

Yeah, pitch alone definitely isn't a cure-all. When we first moved in, our roof was pretty steep, and I figured we'd be fine. But after the first big snowfall, we had ice dams like you wouldn't believe...turns out our attic insulation was practically nonexistent. Once we beefed up the insulation and improved ventilation, things got way better. So I'd say barrier placement is important, but it's just one piece of the puzzle - gotta look at the whole system.

"So I'd say barrier placement is important, but it's just one piece of the puzzle - gotta look at the whole system."

Yeah, totally agree with this. When we first bought our place, I thought the ice barrier was gonna be the magic fix too. Had it installed exactly according to recommendations, but still ended up with ice dams that first winter. Turns out our ventilation was pretty lousy - barely any airflow in the attic. Once we added some soffit vents and a ridge vent, things improved dramatically.

It's easy to get caught up thinking one thing will solve all your problems, but roofs are tricky...everything's connected. Good insulation, proper ventilation, and a well-placed barrier all work together. Sounds like you're on the right track now though - nice job figuring it out.

"Turns out our ventilation was pretty lousy - barely any airflow in the attic."

That's a good catch. Seen plenty of attics where folks nail the barrier placement but overlook airflow. Curious if you noticed condensation issues before adding the ridge vent...sometimes that's an early warning sign.

Had a similar issue at our place - thought the barrier was enough, but started noticing frost forming on the nails inside the attic during winter. Took adding soffit vents along with the ridge vent to finally clear it up. Did you check your soffits too?

- Had the same frost-on-nails surprise last winter... fun times.
- Ice barrier alone didn't cut it here either, ended up adding soffit vents too.
- Definitely worth checking your soffits - ours were half-blocked with insulation, rookie mistake on my part.
- Cleared that up and things improved big time.
- Attics are tricky beasts, always something new to learn, right?

Haha, frost-on-nails club member here too... good times, right? Did you also check your ridge vents? Ours were pretty clogged up - cleaned 'em out and it helped a ton. Attics really keep ya humble, don't they?

"Did you also check your ridge vents? Ours were pretty clogged up - cleaned 'em out and it helped a ton."

Yeah, ridge vents were my first stop too - mine weren't terrible, but I still gave them a good clean just to rule it out. Another thing that really helped was making sure the ice barrier went at least 24 inches past the interior wall line. I initially thought just the eaves would be enough, but extending it further made a noticeable difference. Attics definitely teach patience...and humility, haha.

Good call on extending past the interior wall - I learned that one the hard way. Also, don't overlook valleys and around skylights...ice loves sneaking in there if you're not careful. Attics are definitely humbling, haha.

"Attics are definitely humbling, haha."

Haha, seriously...spent way too many hours crawling around those tight spaces. Good tips above - I'd also add chimneys to that list. Heat melts snow fast there, and ice dams love forming nearby. Learned that lesson the chilly way!

Yeah, chimneys are sneaky trouble spots for sure. I was skeptical at first about needing extra protection around mine - figured the heat alone would handle things - but learned pretty quickly that's not how it works. Had a nasty ice dam form right there my first winter, and let me tell you, chipping ice off shingles in freezing temps isn't fun. Now I'm all about extra barrier layers around the chimney and valleys. Good call mentioning that spot, wish I'd known sooner...would've saved me some numb fingers and frustration.

Yeah, chimneys can definitely catch you off guard. I had a similar issue a few winters back - thought I'd covered all the tricky spots, but totally overlooked the chimney flashing. Didn't realize how quickly ice dams could build up there until I spotted water stains on the ceiling...not a fun discovery.

After that experience, I started making it a habit to run ice barrier at least 2-3 feet around the chimney and down the valleys. First, strip the shingles back around those areas, lay down your ice and water shield nice and flat (no wrinkles or gaps), then reinstall shingles carefully so everything overlaps properly. It's worth taking your time here - rushing can create tiny gaps that cause big headaches later.

One thing I'd add: don't forget about skylights or dormers if you've got them. They can be sneaky troublemakers too. Learned that one the hard way as well.

"One thing I'd add: don't forget about skylights or dormers if you've got them. They can be sneaky troublemakers too."

Haha, ain't that the truth... I thought I was being super thorough last year, but totally spaced on the skylight in our upstairs bathroom. First big thaw and boom - drip, drip, drip right onto the toilet seat. Talk about a rude awakening. Now I'm all about ice barrier around anything that pokes through the roof. Better safe than soggy, right?

Good point about skylights, but honestly, I've found that ice barriers alone aren't always enough. A couple winters back, I had a similar drip-drip situation around my dormer, even though I'd installed ice barrier exactly as recommended. Turned out the real culprit was poor insulation and ventilation in the attic space around it. Once I beefed up the insulation and improved airflow, no more surprise leaks... Sometimes the issue isn't just what's on top, but what's underneath too.

Yeah, ice barrier's great but it can't fix everything. I've seen countless roofs with textbook-perfect ice barriers still leaking because the attic was basically an oven or freezer. Gotta handle ventilation and insulation too, or you're just putting a band-aid on a broken leg...