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I don't recommend using any type of concentrated detergent on a comp roof because it will shorten the lifespan.
A comp roof is mostly composed of petroleum products and applying a de-greaser is the last thing you want being absorbed into the shingles.
 
So far I have seen this 30 seconds spray and walkway cleaner.

Anyone ever used that? Other suggestions?
I tried it. It was not a magic solution. It's just a slightly stronger version of household bleach. It did not affect my moss, nor did it bleach my sidewalk.

I have found Moss-B-Ware to be the most effective.
 
When you look up at an older comp roof and notice the moss free shingles directly below some galvanized flashing, that's the zinc being leached away from the metal and flowing straight down.
I have installed that expensive Z strip under the ridge cap, but found that the sheet of zinc oxidizes after a few years and it becomes mostly ineffective at best, or tears away from wind gusts.
 
I was told that baking soda works well for roofs, Haven't tried it myself but a co-worker says he buys the big boxes at Costco and sprinkles it on the ridges twice a year.
 
It's just the salt in the baking soda trying to kill the moss. Not that effective if he has to apply it twice a year and your gutters won't like it, neither would your lawn if the runoff gets on it.
 
Costco granulated soap.
I don't recommend using any type of concentrated detergent on a comp roof because it will shorten the lifespan.
A comp roof is mostly composed of petroleum products and applying a de-greaser is the last thing you want being absorbed into the shingles.
I use ferrous sulfate for my lawn in the fall or early spring. It kills the moss, but it always comes back by the end of the summer.
I have used powdered laundry detergent, a big bag of Mexican laundry soap you find at Winco for ~$5, but I knew I was replacing my roof soon. It hadn't come back on my roof by the time I replaced it two years later. For the new roof, I think the zinc sulfate will be my choice. I might also use copper sulfate, dissolved into a sprayer, since I have ~15 lbs of it. I have the CuSO4 to use when i'm smelting lead for casting into ingots, it pulls the zinc out of the mix.
 
What I like the best about using pure zinc sulfate, is that it burns the moss completely black.
The last thing you want to do is get up on your roof and try to broom or power wash half dead moss while the roots are still attached to the roof granules.
Once the zinc has killed it dead, just let it be so as not to disturb the roofing. The wind and the rain will eventually dissolve the clumps.
 
I mentioned I would dilute it with water and spray it on sidewalks.
I've tried everything under the sun and found that zinc sulphate worked the best and was the cheapest per lb. to apply.
One of my customers was located in a medical building near OHSU that fabricated limb prosthetics.
A lot of their patients were mobility challenged and keeping the parking lot and sidewalks safe at all times was a big challenge.
 
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One thing to be mindful of is that salt based solutions will corrode metal. Repeated applications will eventually cause noticeable damage to things like gutters and railings. The various sulfate solutions can be corrosive to other media, for example zinc sulfate can damage tar based roofing tiles. Zinc oxide does not, but is less effective on bulk moss than the sulfate version. Iron sulfide attacks copper and zinc coatings. Copper sulfate will corrode nearly any metal.

The point here is that you have to look at your application, and if you have moss on multiple surfaces you probably need multiple products to deal with it. Also many of these products are a general herbicides, so you need to be careful how they are applied if you don't want to damage other landscaping. Moss is generally more susceptible than other plants, though, so a low enough concentration will only kill off the moss. But you do need to be mindful that the other plants will not like it. If they are already stressed from something else even a low dosage could end them.

As for the OP, most of this stuff is fine on concrete and wood. It may cause discoloration, depending on how concentrated the application is, but that is about it. I am unaware that any of these products are specifically damaging to concrete.
 
Wet, apply Sodium hyperchloate solution and let sit, soft per was rinse and allow to dry. Find a clear concrete sealer and apply. (Get at masonry store)
 
a 50\50 mix of water and vinegar as posted always works for me, then spray it off. If using a power washer, it's easier, This is the most cost efficient
 

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