I started on one of my summer to do projects yesterday. The north side of my roof is pretty mossed up. The south side looks fine.
Since the roof is older, I decided no to power wash it and hopefully extend the roof's life a bit.
The moss is really dry and easily comes off with a very light scraping.
I figure about five hours time to get most of it off.
Once I remove, I like to treat it as I know I can't get every bit of it and it will come back.
Any suggestions on what to treat a composition roof from the PP moss experts?
I've heard Powder Tide, 50 /50 beach water....
Thanks for your input.
SF

Before scraping




After scraping

whats the pitch on your roof?

Not sure what that is in the pic. Not a patch though. No patches on my roof.

Sorry, misread that.
Not a steep pitch. Good old 50's rambler.
I have a zinc strip on it now. It worked well for a few years, but isn't doing much now.

Moss proof. Green can, red writing. Red top. Sprinkle along the peak. Done.

What Dogfish said...

Power washing and scraping removes material from composition tiles and is counter productive if you want it to last longer. The best time to treat moss is when it is actively growing during Fall or Spring weather.

If the moss is really bad and clumpy, you can broom it off gently, use a blower to clear it off and then chemically treat the roof.

Moss off or whatever it's called is toxic to pets, regular powder soap for clothes will do the same thing and your pets will not ingest it and die.

Cheap, easy and simple.


Fishy

Moss Out will work too, as will any Iron Sulfate (Ferrous Sulfate)... Zinc works too, as well as Copper, but be very very careful the products you use with Zinc and Copper in them, as well as the Iron, they can and will leech into streams and kill fish... its not really about the amount used in your situation since alot has been removed, its the coverage... if you live by streams on your property or have beach front property pay attention .... far away, you can use a little more, but dont go past the recommended use... i can use half of what is recommended and still get the same results...

the reason i asked the pitch, is it can and will help you in killing it off, heavier on the ridge, light light at the soffits use the pitch to spread it down the roof...

you could always get some Zinc strips like you have but new, or Copper, but they are more expensive now....

as Andy said, Moss Proof works great too, people will spray it for like 150ish... FYI on Iron Sulfate stuff, Iron Sulfate will turn stuff red, like rust... so pay attention... it has to be there for a bit, but it can and will, and is a pain in the ass to remove....

A word of warning about powdered moss killer you shake out of a can. I did Stonefishe's project on my Mom's roof last summer and when done bought a can of moss killer to shake on the peak of the roof as a future preventative. The brand name slips my mind and the can is long gone but it was tall, round and I believe, purchased at home depot.

It was a warm day with a bit of a breeze. I'm in jeans, tshirt, romeos and ball cap. When I got home I had a reaction from all the moss killer dust that float through the air and landed on me. my face was flushed and red for about 2 weeks and itched a great deal. I figured since I was sweating some, the dust got on the sweat soaked liner of my hat and worked it's way down my face. The whole experience was pretty uncomfortable. The spooky part was as I applied the stuff on the roof, there was no indication that I was getting any on me. It was bad enough I threw away the clothes and hat as I didn't want that $hit getting in my washing machine.

Be careful!