I get the hesitation with spray-on treatments, especially if you’re collecting rainwater. I’ve seen a few “eco” brands claim to be garden-safe, but when you dig into the fine print, there’s usually a warning about runoff or residue. Honestly, I’m not convinced any of them are totally risk-free for long-term use.
One thing I’ve noticed on inspections: folks who keep their roof clear of debris and trim back overhanging branches seem to have way less algae and moss, even without chemicals or metals. It’s not a magic fix, but sunlight and airflow make a bigger difference than most people expect. If you’re dealing with a steep pitch, it’s a pain to keep up with, but it might be safer for your warranty and your garden in the long run.
I get the appeal of copper or zinc strips, but like you said, they’re hit-or-miss on steeper roofs. Sometimes the simplest approach—regular cleaning and maintenance—ends up being the least risky, even if it’s more work.
I’ve noticed the same thing about keeping the roof clear—my uncle’s place is surrounded by big maples, and when he finally started trimming them back, the moss problem basically disappeared. He tried zinc strips too, but on his steep roof, the runoff just didn’t reach far enough. I’m curious, has anyone tried those newer algae-resistant shingles? I’ve seen Atlas tout their Scotchgard tech, but I wonder how it holds up after a few seasons, especially in shady spots.
We’ve got a few buildings with those Atlas shingles—Scotchgard and all. I’ll say, they do a decent job for the first couple years, but in spots that never see sun (think north-facing slopes under big trees), you still get some streaks after a while. Not as bad as the old stuff, but not magic either. Honestly, nothing beats just keeping branches trimmed back and gutters clear. I wish there was a true “set it and forget it” roof, but I haven’t seen it yet...
I wish there was a true “set it and forget it” roof, but I haven’t seen it yet...
Same here. I put Atlas on my shed thinking the Scotchgard would be a game changer, but after two winters in the shade, I’m still scrubbing streaks. Has anyone tried those zinc or copper strips along the ridge? Wondering if that actually helps or just another gimmick.
