Moss removal

Google "how to remove moss from shingles".

I'd replace the shingles.

I'd try a product called Wet & Forget. I've had great results with it on my aluminum siding. It goes on with a garden sprayer. It doesn't work instantly, but once on the moss should come off in time with wind and rain. Avoid it if possible, but be careful when working on a roof. Plan your spraying so you are always standing in a dry section.

Do some digging around on google, as moss is in its own world. Basically moss is everywhere and you have to change its growing conditions. Think of moss as a weed. Grows everywhere and a pain to get rid of. To get under control, there are several products available at big box hardware stores. And it takes longer than what I thought it would take. Then once under control make sure to the maintenance to keep it under control. I have about 1/4 of my roof that never see daylight so lots of moss. Once under control I sprinkle powered laundry soap about 3 times a year to keep under control. Liquid dish soap spray'd out of a garden sprayer also helps. Or spend the money and install zinc strips. But they are somewhat hard to put or keep in after roof has been installed. Atleast mine.

I also do my rv with dish soap. I open up awning and spray it and roof and let it soak for awhile then hose off.

I used to use a pressure washer. Not anymore. If you do, use largest angle head you have. I use a 40 degree and don't let spray hit with much pressure. But may problems with pressure washer.
1. Gets slippery and you're up on the roof.
2. Dragging hose around make black marks when hose comes over edge.
3. Get to close with spray and you've just added to your problems, not solved them.

In Oregon we sprinkled powdered Tide laundry soap on the roof of our house, it kills the moss.

Here in Florida the "professionals" power wash shingle roofs all the time.

Otherwise all you'd see when you came down to Florida would be black streaked or green roofs!! :B

Moved from Forum Technical Support

Zinc flashing at the top row of shingles will keep it gone, a punch broom will get rid of most of it and the zinc will clean it off in time

Use any kind of Deck Wash that doesn't have chlorine.

I've been doing that for years on a shady part of the cottage roof and it works like a charm. Once it's dead and brown sweep it off.
I re-apply every couple of years to keep on top of it.
I use a cheap garden pump sprayer.

Mortimer Brewster wrote:
I'd try a product called Wet & Forget. I've had great results with it on my aluminum siding. It goes on with a garden sprayer. It doesn't work instantly, but once on the moss should come off in time with wind and rain. Avoid it if possible, but be careful when working on a roof. Plan your spraying so you are always standing in a dry section.

Used this product at home on moss and here in Fl on our concrete. Works great but don't expect result instantly it takes a few months for it to eat the moss.