Copper definitely works, but yeah, the price is tough to justify unless you’re dealing with a high-end install or historic property. Zinc strips are a decent compromise—though I’ve seen mixed results, especially in areas with heavy rainfall or shade. Out here in the Midwest, humidity really does a number on shingles, no matter what the packaging claims. Have you noticed any issues with fastener corrosion or shingle lifting after installing zinc? Sometimes I see that if folks don’t use the right nails or sealant.
I’ve had zinc strips on my place for about three years now. Haven’t noticed much shingle lifting, but I did get some rust stains around the nails the first year. I probably should’ve used stainless instead of whatever cheap ones I had on hand. Midwest humidity’s brutal—algae still creeps back in the shadiest spots, even with the strips.
Interesting you’re still seeing algae even with the zinc strips—humidity really does make things tricky. Did you install the strips just at the ridge, or did you run them lower down too? Sometimes I’ve seen folks double up in the worst spots, especially on north-facing slopes. Have you ever tried copper strips instead? They’re pricier but seem to last longer in my experience. Just curious if you noticed any difference in runoff patterns or staining where the algae keeps coming back...
- Had a similar issue last year—zinc strips just at the ridge didn’t cut it for me either.
- Ended up adding a second row about halfway down on the worst (north-facing) section. That slowed the algae, but didn’t totally stop it.
- Tried copper strips on one side as an experiment… pricey, but honestly, they seem to work better and haven’t stained the shingles much.
- Haven’t noticed odd runoff patterns, but I do get a faint metallic streak after heavy rains. Not super noticeable from the ground, though.
- Humidity here (coastal SC) just makes everything harder… I’m still hunting for a long-term fix that doesn’t involve constant cleaning.
Tried copper strips on one side as an experiment… pricey, but honestly, they seem to work better and haven’t stained the shingles much.
Copper definitely outperforms zinc in my experience too, especially in high-humidity zones like coastal SC. The ions released from copper are just more effective at inhibiting algae and moss growth. That said, the cost is a real consideration—copper prices have gone up a lot lately.
One thing I’ve noticed: placement matters almost as much as material. If the strips aren’t exposed enough or if there’s debris buildup (pine needles, etc.), you lose a lot of the benefit. I’ve seen some folks try wider copper flashing to get more coverage per rain event, but it can be overkill unless you’re dealing with really persistent algae.
The faint metallic streaks after heavy rain are pretty normal and tend to fade over time. As for long-term fixes, some newer shingle products have copper granules embedded right in them—might be worth looking into when it’s time for a re-roof. Until then, regular maintenance seems unavoidable in this climate... frustrating but true.
