Even with good flashing, isn’t there still a risk of leaks down the line, especially if you get a heavy storm or ice dam? I’ve stuck with gable fans mostly because I’m paranoid about cutting into the roof deck.
I totally get where you’re coming from—cutting into the roof feels like tempting fate sometimes. But I’ve had a solar roof fan on my own place for about six years now (asphalt shingles, midwest winters), and honestly, no leaks yet. I was super picky about the install, though—triple-checked the flashing, made sure the sealant was high quality, and kept an eye on it after big storms.
What surprised me is that my neighbor’s gable fan actually let in more wind-driven rain than my roof unit ever has. Turns out, the way his siding overlaps left a little gap that water found during a sideways thunderstorm. Fixing that was a pain.
I guess my take is, both setups have their quirks. Roof penetrations are scary, but with careful install and regular checks, they can hold up just fine. Gable fans are easier to patch, but they’re not always immune to leaks either, especially if your siding isn’t perfect or you get wild weather. I’d say it’s less about being too cautious and more about what you’re comfortable keeping an eye on over time.
That’s interesting about the gable fan letting in more rain—never thought about the siding being a weak spot. Have you noticed any difference in attic temps or humidity between the two setups? I’m curious if one actually outperforms the other long-term.
In my experience, roof-mounted fans tend to keep attic temps a bit lower, especially in hotter climates, since they’re closer to the heat source. Gable fans can sometimes struggle with airflow if intake vents aren’t balanced. Humidity differences are usually minor, but I have seen roof fans help more with moisture after heavy rains—assuming the install’s tight and there’s no backdraft. Long-term, it really comes down to how well everything’s sealed and vented. If the gable fan’s letting in rain, that could lead to bigger issues over time than just temp swings.
Long-term, it really comes down to how well everything’s sealed and vented.
That’s definitely true, but I’d push back a bit on roof fans always being the better choice for moisture. In some cases, especially with older homes or those with complex rooflines, adding more penetrations up top can actually increase the risk of leaks over time—even with a solid install. I’ve seen gable fans paired with well-sized soffit vents work just as well for airflow and humidity, provided the intake/exhaust balance is right. Sometimes it’s less about fan placement and more about the whole system working together.
- Good point about roof penetrations—I've had to deal with a few leaks on older tile roofs after adding fans, even with pro installs.
- Gable fans plus soffit vents can definitely work if the intake/exhaust is balanced.
- It really does come down to the whole system, not just one component.
- Sometimes, less is more when it comes to cutting into the roof... especially if you’re managing an older property.