I’ve had similar luck with zinc strips—slowed the moss, but didn’t wipe it out. On my place (asphalt shingles, Pacific Northwest), keeping the roof clear of debris and trimming back overhanging limbs made the biggest difference. The shade just keeps things damp otherwise. I’ve read copper strips can be a bit more effective than zinc, but haven’t tried them myself.
I tried copper strips a couple years back, mostly out of frustration after zinc didn’t really do the trick. Honestly, I didn’t see a huge difference—maybe a bit less moss, but it sure didn’t keep the roof spotless. My place gets a ton of shade too (Western WA), so once that moss takes hold, it’s a battle. Like you said, clearing off pine needles and trimming back limbs seems to give the most bang for your buck.
One thing I noticed: if you let debris pile up, even a fancy metal strip won’t save you. The moisture just hangs around. I get why folks like the idea of copper, but if your roof’s always damp, seems like you’re just slowing things down, not stopping them. I’m not convinced there’s a perfect fix for moss out here—just a lot of little things that help a bit.
Copper and zinc strips are one of those things that sound great in theory, but in practice—especially in the Pacific Northwest—they’re more like a slow-down than a fix. I’ve seen a lot of folks get their hopes up, only to be disappointed when moss keeps creeping back. You nailed it about shade and debris. Out here, even the best metal strip can’t keep up if the roof’s always damp and covered in needles or leaves.
What I usually tell people is, think of moss control as a whole routine, not a single product. Here’s how I look at it, step by step:
1. **Stay on top of debris**. Like you said, if pine needles or leaves pile up, moisture just sits there. I’ve seen roofs where the moss is actually growing on top of the debris, not even the shingles. Blowing or sweeping it off every couple months—especially after big storms—makes a huge difference.
2. **Trim back overhanging branches**. More sun and airflow means a drier roof, and moss hates that. Sometimes you can’t get full sun, but even a little helps.
3. **Copper or zinc strips**. They do help, but only as part of the mix. I’ve noticed they work better on steeper roofs, where rainwater actually washes the ions down the surface. On low-slope roofs or spots that stay wet, it’s less effective.
4. **Manual removal**. For stubborn patches, sometimes you just have to get up there (safely, obviously) and brush it off. I use a soft brush, nothing too abrasive.
5. **Preventative treatments**. Some folks use moss-killing sprays in early spring or late fall. They’re not magic, but they can slow things down.
I get the frustration—there’s no silver bullet, especially here where it’s wet nine months out of the year. But you’re right, a bunch of little things add up. I’ve seen roofs where just keeping up with debris and trimming trees made more difference than any product.
If it helps, you’re definitely not alone. Most of my clients in western WA have made peace with a little moss here and there. The main thing is keeping it from getting thick enough to damage the shingles or cause leaks. That’s the real battle.
Totally agree—there’s no magic fix for moss around here. I’ve got a couple buildings with low-slope roofs, and honestly, the copper strips barely made a dent. What’s helped most is just keeping up with the debris and trimming back the trees. It’s not glamorous, but it works better than any product I’ve tried. I do wish there was an easier way, though... climbing up there every few months isn’t my favorite hobby.
- Totally get the frustration. That line—
—hits home for a lot of us.“climbing up there every few months isn’t my favorite hobby.”
- Copper strips are kind of hit or miss, especially if you’ve got a lot of shade or tree cover. I’ve seen them work on steeper roofs, but low-slope seems to be a different beast.
- Debris and overhanging branches are huge factors. Even just a few extra leaves can trap moisture and make moss worse.
- Not glamorous at all, but honestly, regular clearing is what keeps my own roof from turning into a science experiment.
- Ever tried using a leaf blower instead of climbing all the way up? Not perfect, but sometimes it’s enough to knock off loose stuff from the edge.
- I do wonder if anyone’s had luck with those zinc powder treatments. I’ve heard mixed things, but never tried it myself.
- At least you’re ahead of the game by staying on top of it. Most folks wait until it’s a full carpet up there... then it’s a nightmare to fix.
- If you ever find that “easier way,” let us know. I’d be first in line.