“Copper and zinc can help in theory, but like you said, those strips don’t always live up to the hype—especially under heavy shade and constant moisture.”
That’s been my experience too. I’ve seen a few jobs where the homeowner swore by zinc, but after a couple winters, moss was right back at it. Out of curiosity, have you noticed any difference in how fast algae or moss comes back depending on shingle color or texture? Sometimes the darker shingles seem to hide it better, but I’m not convinced they actually slow growth. Just wondering if you’ve seen anything similar.
Sometimes the darker shingles seem to hide it better, but I’m not convinced they actually slow growth.
I’ve noticed the same thing. Darker shingles definitely make the stains and moss less obvious, but from what I’ve seen, it doesn’t really stop the growth. Did a job last fall where the homeowner had black Atlas shingles—looked clean from the street, but once we got up there, there was a ton of moss tucked in the shaded spots. The lighter roofs just make it more obvious, especially after a few wet seasons.
Texture seems to matter a bit too. The rougher, more dimensional shingles seem to give moss more places to hang on. On smoother ones, it’s easier to brush or rinse off. But honestly, if you’ve got big trees and not much sun, nothing really keeps it away for long. Even those zinc strips don’t do much once you hit two or three rainy seasons in a row. Just my take from what I’ve seen so far.
Even those zinc strips don’t do much once you hit two or three rainy seasons in a row.
Yeah, I’ve seen the same thing—zinc strips are like putting a band-aid on a leaky dam if you’ve got heavy shade and constant moisture. I swear, moss is like that one neighbor who never gets the hint to leave. Texture definitely matters too. Those architectural shingles look great, but man, they’re like a moss hotel. Ever tried using a leaf blower after a dry spell? Not perfect, but it’s oddly satisfying.
I hear you on the zinc strips—once you’ve got a few years of wet weather, they just can’t keep up. I’ve seen a lot of folks surprised by how fast moss takes over, especially on those textured architectural shingles. They look sharp, but all those nooks and crannies are perfect for moss and algae to dig in.
I’ve had some luck with a soft wash using diluted bleach (careful with landscaping below), but it’s more of a maintenance thing than a cure. The leaf blower trick after a dry spell is oddly satisfying, but it’s really just surface stuff—anything rooted in is going to stick around. One thing I’d add: if you can trim back any overhanging branches, even just a little, it makes a big difference. More sun and airflow helps the roof dry out faster after rain.
If you’re dealing with constant shade and moisture, sometimes it’s just about managing expectations and keeping up with regular cleaning. Haven’t found a true “set it and forget it” solution yet, especially in the Pacific Northwest...
Yeah, trimming back branches made a bigger difference than I expected. I used to think it was all about the chemicals, but just getting more sunlight on the roof helped slow down the green fuzz. Still, like you said, nothing’s really permanent—just gotta stay on top of it. Those Atlas shingles look great but man, they’re like moss magnets in our weather.