Advice about my roof

[Steven Hockstein]

My roof was replaced twelve years ago. There is a shaded area at the rear of the house ( about 25' wide) where some moss is growing. My neighbor's trees are shading the roof and I cannot trim them.

My plan is to have the moss cleaned and install zinc strips along the ridge in the area where moss has grown.

Does anyone have experience with this. Is the zinc effective after the moss has already grown on the roof?

It is interesting to see that no moss has grown in the areas directly under the chimney where there is copper flashing or under the metal power vent.

[hausdok]

Hi Steven,

They work, but only for a short distance. Around here they seem to keep the algae and moss off the shingles for about four courses and after that it's game on. I suppose you could install them every four or five courses and have a tiger-striped roof, though.

ONE TEAM - ONE FIGHT!!!

Mike

[allseason]

You are commonly allowed to cut any limbs that hang over your property, at the property line.

Try a 10% bleach solution sprayed over the affected area. It will kill the moss and the rain will slough it off. I find that the moss does not pull the granules the way lichens do, so you can try pulling some of to see if it does any damage. If no damage occurs you can sweep it off, it usually comes off with ease.

I have heard the same with the zinc, it has to be installed every few courses.

[Chad Fabry]

A church near me has copper roof vents near the ridge. The area ( maybe 40 ft to the eave) below the vents is stain free and looks new. The rest of the roof is covered in moss.

My smoke house and porch both have cedar shingles and copper caps that I installed maybe 15 years ago. Neither has anything growing on the surface or at the drip line on the soil.

Copper sulfate is a very effective herbicide and algaecide.

[kurt]

I've used a copper powder normally used for orchard fungicide and had very good luck with it. It's called MicroCop. I don't know if it's still available; I've had a big can of it for a long time.

I've used it to get rid of some roof moss; it was effective.

Fabry, have you ever heard of MicroCop?

[Chad Fabry]

I haven't heard of MicroCop. I have used micronized copper azole, and micronized copper sulfate.

update: It took a minute but I found the MicroCop MSDS. It's listed as a fungicide and it is copper sulfate.

[Scottpat]

I have a home that I have been doing the draw inspections on for about the past year and they installed copper strips in various locations around the roof. At first it looked funny, but now the cooper has a patina that blend in with the shingles.

I'm not sure if I would do much to a 12 year old roof if they are asphalt shingles.

[Steven Hockstein]

I have a home that I have been doing the draw inspections on for about the past year and they installed copper strips in various locations around the roof. At first it looked funny, but now the cooper has a patina that blend in with the shingles.

I'm not sure if I would do much to a 12 year old roof if they are asphalt shingles.

My roof is in otherwise good condition. I anticipate another ten years before replacement is needed. There is just a small section with moss. The moss is not too bad yet. I want to take care of the problem before it gets really bad.

I cannot do anything about the shading because the trees are along the property line and do not really hang over the house. The shading is a result of the orientation of the house.

[hausdok]

Buy a gallon of liquid swimming pool cholorine, pour it into a pump sprayer, add a pint of dove liquid dishwashing detergent and fill the rest with warm water. Some evening when dry weather is predicted overnight, wet the mossy area down with the solution. In the morning, rinse it off with a garden hose. Don't get it on the shrubs or flower beds or you'll be replanting.

ONE TEAM - ONE FIGHT!!!

Mike

[Marc]

Buy a gallon of liquid swimming pool cholorine, pour it into a pump sprayer, add a pint of dove liquid dishwashing detergent and fill the rest with warm water. Some evening when dry weather is predicted overnight, wet the mossy area down with the solution. In the morning, rinse it off with a garden hose. Don't get it on the shrubs or flower beds or you'll be replanting.

ONE TEAM - ONE FIGHT!!!

Mike

I do something similar for the Gloeocapsa on roofs. I use clorax instead, 2 cups per gallon of water. I dampen the surfaces well with a water hose instead of adding detergent because the detergent reacts with some of the active ingredient in the clorax, sodium hypochlorite, to neutralize it.

Like Mike, I do it in the evening in high humidity to keep it moist as long as possible. The chlorine is unstable beyond a concentration beyond about 15%-20% and will leave the solution if too much water evaporates. Exposure time is one of the factors that determine how well it works. Household clorax is usually 6% sodium hypochlorite.

Another thing that makes the chlorine leave the solution is agitation so I use a plastic watering can to gently dispense it. Works great. Moss on roofs is rare here so I don't know how well it would work on that.

This method hasn't ever killed any vegetation, well, maybe just a little grass on the drip line. The chlorine is just about gone before any leftover solution drips off the roof anyway.

Marc

[hausdok]

Hi Mark

When I said "swimming pool bleach" I was referring to sodium hypochlorite but the exact name slipped my mind at the time of typing - seems to happen a lot lately - so I substituted bleach. It's actually a lot more aggressive than ordinary Clorox.

ONE TEAM - ONE FIGHT!!!

Mike

[Kyle Kubs]

My experience is the same as Chad's. Half of the houses I inspect are in the woods & I commonly see a clear path down to the eave under a galvanized or copper flashing.

Mike's climate is a lot more temperate than ours. Our winters and dry seasons make the moss a lot more docile here. The last firewood shed I built with a cedar shingle roof, I put a Copper ridge on it and there has never been any moss on it, fully shaded 95% of the time.

As far as killing the existing, I go with a little more gentle approach, having a preference for Borate solutions rather than Chlorine. I have no issue if it takes a few or more days to finally die. The copper sulfate probably just as good.

[John Kogel]

A copper strip will last for many years, until it gets stolen, maybe. Zinc strips I think are plated steel, as they seem to lose potency after a few years.

A word of caution about spraying soap on any roof. A guy I know woke up from a 3 day coma after forgetting he'd sprayed soap on his shingles. He must have done a 3-point landing, broke both his wrists and his collarbone as well as getting a nasty concussion.

I think dry agricultural lime will kill moss if you hit it hard enough. I'm going to be trying that on my place.

[Chad Fabry]

I finally took 30 seconds to snap a photo. North slope- it's pretty clear that tiny bit of copper is toxic to moss and algae.

Click to Enlarge

36.71 KB

[Greg Booth]

...............great shot, thanks.........Greg

[Steven Hockstein]

I filled a garden sprayer with a solution of TSP powder mixed with water and bleach. I sprayed the roof and let it sit for a few minutes. I gently swept the shingles with a soft broom (the TSP foamed-up a little) and then repeated the spraying.

After waiting another few minutes I hosed off the roof and the fluid that came off was dark brown/green.

Now three months later the shingles look good and no new growth.

[Tom Raymond]

At least that church still has some copper on it, there's another not far from you that went with faux copper painted corrugated steel. It's lovely.

The best kept church here still has it's slates, the rest have gone asphalt.

[Chad Fabry]

At least that church still has some copper on it, there's another not far from you that went with faux copper painted corrugated steel. It's lovely.

The best kept church here still has it's slates, the rest have gone asphalt.

Yeah- it's an awful roof on an otherwise beautiful building. I'll snap a photo.

[Brandon Whitmore]

I finally took 30 seconds to snap a photo. North slope- it's pretty clear that tiny bit of copper is toxic to moss and algae.

I see that same look below rusted galvanized vents and flashing...

[allseason]

I'm putting new shingles on my roof next spring and I'm going to install the zinc strips. I have now, after 22 years, all kinds of gleocapsa staining, lichen and moss growth on the northeast side, but not under the galvanized plumbing vent pipes on that side. The zinc coating on the pipes is definately making a difference. Even if the strips look funky it'll better than the organic growth.

[Jerry Simon]

I'm putting new shingles on my roof next spring and I'm going to install the zinc strips. I have now, after 22 years, all kinds of gleocapsa staining, lichen and moss growth on the northeast side, but not under the galvanized plumbing vent pipes on that side. The zinc coating on the pipes is definately making a difference. Even if the strips look funky it' better than the organic growth.

Aren't they making copper-impregnated shingles now for this?

[Rob Amaral]

Lead does a great job 'leaching out' to stop these issues.. and yes.. You usually are 'allowed to trim overhanging trees over your property in most 'worlds'..

Just ask the guy..

[allseason]

Aren't they making copper-impregnated shingles now for this?

From what I've heard that lasts about 5-10 years, just when the gleocapsa presents itself, along with the rest of the growth. Don't count on it.

[Edward Peterson]

My roof was replaced twelve years ago. There is a shaded area at the rear of the house ( about 25' wide) where some moss is growing. My neighbor's trees are shading the roof and I cannot trim them.

My plan is to have the moss cleaned and install zinc strips along the ridge in the area where moss has grown.

Does anyone have experience with this. Is the zinc effective after the moss has already grown on the roof?

It is interesting to see that no moss has grown in the areas directly under the chimney where there is copper flashing or under the metal power vent.

Do you have a photo of your roof that indicates the problem your trying find a solution for?

[hausdok]

Hi Ed,

You might check out the date of that OP. That was seven months ago. I'd bed he's fixed it by now.

ONE TEAM - ONE FIGHT!!!

Mike