I hear you on zinc strips not being a cure-all. I’ve got a couple older duplexes with low-slope roofs and moss is just relentless, no matter what I try.
Couldn’t agree more. I’ve seen tenants try to “help” and it never ends well... For anything above a single story, I just budget for pro cleaning every couple years—cheaper than an ER bill.“for steep or high roofs, pros are worth it. The risk just isn’t worth a tumble.”
Funny, I’ve tried the zinc strips too and had the same issue—moss just laughs at them here in the PNW. Ever look into planting sedum or other green roof options? I know it’s not for every building, but I’ve seen a few low-slope roofs stay cleaner with them. Wonder if that’s just luck or if the extra coverage helps crowd out moss...
Moss in the PNW is basically a supervillain—zinc strips, copper, you name it, it just shrugs and keeps growing. I’ve seen sedum work on some low-slope roofs, but it’s hit or miss. Sometimes the moss just finds a way to sneak in around the edges anyway. Still, gotta admit, those green roofs look pretty cool when they take off.
Moss in the PNW is basically a supervillain—zinc strips, copper, you name it, it just shrugs and keeps growing.
Totally get this. I tried scrubbing and spraying my own roof last fall, but the moss just laughed at me and came back twice as thick. It’s kind of wild how persistent it is. I’m still figuring out if hiring someone is worth it or if I should just keep at it myself. Either way, those green roofs do look awesome when they work... even if the moss tries to crash the party.
the moss just laughed at me and came back twice as thick
That’s been my experience too, especially with the north-facing side. I’ve tried zinc strips and even a pressure washer (which I later regretted—took some granules off the shingles). Honestly, I’m still not convinced hiring out is always worth it unless you’ve got a really steep pitch or a big roof. The cost adds up fast, but so does the time if you’re doing it yourself. Either way, it’s a constant battle in this climate... sometimes I wonder if the moss is just part of living here.