Anyone have a user-friendly way to rid our three-tab roofing of moss? We are hoping for a solution somewhere in between scrubbing it off with a brush (time-consuming) and zapping it with napalm or equivalent chemistry (not environmentally friendly!)

I have heard bleach, ammonia, zinc, etc. Not sure the applications, or if they are harmful, too. (I guess it's all relative....just want the least impact for the least time.)

I can't wait until we can legitimately ditch this roof. We have metal roofing on everything else and don't have this problem with those roofs. However, this roof is only seven years old so we have a long time to wait! Hey, maybe we should just let the moss accumulate! (NOT...)

Thanks in advance for your replies.

-- sheepish (WA) (rborgo@gte.net), March 18, 2001

Answers

if you have moss of the 3 tab roof,, it means its not getting a chance to dry out. Shaded by trees,, or what ever. which will cut down on the life of the roof. The only thing I found that works while I was roofing,, is a herbicide for moss,, but DONT spray the whole roof,, just do the last 2 rows or so,, its work its way down and kill it. Try to do it at least 3 days before the next rain,, to keep it from washing off. A blow torch would work to kill it, as long as you dont start melting the shingles. CAn you cut down what ever is blocking the roof? if you do that,,itll take care of itself

-- Stan (sopal@net-port.com), March 18, 2001.

use of a copper wire along the ridge or a zink strip will take care of it the residual copper or zink will kill the moss and is rather harmless to the enviorment and last indefinatly

-- george darby (windwillow@fuse.net), March 18, 2001.

If it makes you feel better, ammonia is pretty much pure nitrogen, and if it runs off into your yard, it probably won't hurt it too much, especially if it rains soon after.

-- Soni (thomkilroy@hotmail.com), March 18, 2001.

I found that a coarse bristle push broom does well to initially remove the moss quickly.

They sell zinc flashing strips (about 2" wide, although other widths may be available) more cheaply than copper as a rule. We retrofitted the old barn roof with the zinc, tucking it in under the top row of shingles to hold it in place and leaving enough exposed from the bottom edge of the shingle so the rain water would wash over it and prevent it from regrowing. I haven't noticed any problems with the ground where the water drips onto, except that moss isn't growing there anymore either.

On a side note, I collected up all the moss I scraped off and put it into a shady area that I didn't want to try mowing (too inaccessible) and have started a moss garden growing there. Looks great, low maintaince, in an area where nothing much would grow anyway.

-- julie f. (rumplefrogskin@excite.com), March 18, 2001.

Living in mossville (Oregon), this is a frequent problem people have. I've HEARD that a galvanized ridge cap will prevent moss build up everywhere down slope. I HAVE witnessed several roofs which are otherwise covered with moss, which have no moss below galvanized chimney flashing; this makes me suspect that it works. Never tried it myself; I'm also fond of metal roofing. I have to use baked enamel roofing, rather than the galvanized roofing for a lot less $, due to my wife's color sensitivity....

I don't know if adding galvanized flashing AFTER there's already moss on the roof will kill it in a timely fashion, but it's worth a try.

JOJ

-- jumpoff joe (jumpoff@ecoweb.net), March 18, 2001.

Thanks! Stan, actually nothing is blocking it, except the clouds (or the house roofline itself...mostly it's on the north side!) Well, maybe the woods across the road from us. It's just really wet around here most of the year and even this year, with our "drought" we have a lot of moss. (Western Washington State, another mossy spot like where JOJ lives in OR.)

I like all the ideas; showed 'em to my spouse (who prompted me to ask the question.) We'll mull over the options and see what we can do. The zinc strip or version thereof, sounds interesting. If we mechanically scrape, bleach, ammonium-ize, or whatever, it sounds periodic. But something that would continue to work after an installation/application sounds promising.

Or we could move to a drier climate!

Thanks again.

-- sheepish (WA) (rborgo@gte.net), March 18, 2001.

Hi, Sheepish. We have to treat the roofs of federal buildings in april and november with sodium bromide which I understand is a close relative to bleach. We just spray it on and let sit, then they wait for several rains that rinse it off. Seems to work. The black and green areas turn back into white stone. Typical government operation, build a building with depressions and low spots in it's flat roof. Go with the lowest bidder... Then pay seven or eight new pipers later on when the moss, and other problems show up, and the moldy odors come through the air handlers... Never a dull moment.

-- The Action Dude (theactiondude@yahoo.com), March 18, 2001.

I noticed that another thread talks about the miracles of vinegar to kill Canadian thistle -- it seems to be more effective than Round-up. Perhaps you might give vinegar a try.

-- snoozy (allen@oz.net), March 19, 2001.

Might try copper sulfate solution, like they use to get rid of that suff in swimming pools. Can use the blue crystals to rub on the moss or maybe a solution and pour it on the moss.

-- Desert Dry (shafteryachtclub@yahoo.com), March 19, 2001.

Not sure of the best way to keep moss from growing on a roof, but the best way to get it off once it's there is a pressure washer. Just make sure you only spray in a direct line from the ride to the eave so water is never forced under the shingles.

-- Skip Walton (sundaycreek@gnrac.net), March 19, 2001.

I have a heavy moss problem and tried a product that would kill the moss, applied it twoce last year but it did nothing. A month a go i put zinc strips on all the roof peaks, I am waiting?

-- Howard C. Williams (redgate@echoweb.net), March 20, 2001.

Moss will not grow on NEW concrete (because of the lime -- alkaline). To make moss grow, you need an acid environment (yes, some people do grow it on purpose -- moss gardens). Therefore, I think vinegar would not work and might even make it worse.

I think you will have to scrub it off. Then I would try making a strong solution of baking soda and spraying the roof, and I would put up the zinc strips. There are shingles with copper granules embedded, but they are more expensive, naturally, and besides, you don't want to use shingles when you reroof. I am thinking that the zinc strips will prevent recurrance of the moss, but might not be enough to kill an already large population of moss.

-- Joy F (So.Central Wisconsin) (CatFlunky@excite.com), March 20, 2001.

I had moss on 3-tab for years. I sawed a copper water pipe to get the copper dust left by the saw cuts. I spred this over the (low pitch) roof and 6 months later the moss was gone!

-- Gregg (none@aol.com), April 14, 2002.